SuttaCentral
When one investigates the Dhamma with clear comprehension, they relish every opportunity to meditate. Seeing the results of this practice, the serious person seeks seclusion for most of the day and most of the night.
To the outsider, this may look a lot like doing nothing.
How would you counter the observation that Buddhists “do nothing” all day?
For those of you who have hobbies, how you maintain a mind that is free from hindrances, and/or make meaningful an impermanent worldly activity?
Buddhism is fun because it takes one to the part of the mind where the Spiritual aspect Awakens. Living the Holy Life is rewarding and fun. The time spent in practice for many is the best time of the day. We just have tend to found out how unfun mundane life was, before the Dhamma.
I wouldn’t. A lot of schools and teachers would say “Exactly!” 
Doing nothing is fun. Not feeling the rush & anxiety of the ratrace, being content, being able to stop; these are all virtues lost in the rush-rush do-all age.
They may have very good relationship with ‘emptiness’.
I would ask them whether they’ve built a monastery recently.
Why be concerned with how outsiders view it?
I never saw meditation as doing nothing.
I started with meditation before Buddhism. I’ve always found it interesting, and later, the dhamma too. The question of “fun” never came into it. I guess anything that absorbs your interest is “fun”.
Beyond that, religion, in-general seems to have a problem with anyone having a good time, though for different reasons with different religions.
Some hobbies I don’t see as fitting in with lay Buddhists, but to be fair I never did those hobbies.
And emptiness is a great way of relating with nature!
The two go hand in hand. 
If you mean those words as they tend to meditate, or prefer seclusion then that is appropriate. But suttas state that taṇhā (craving) mixed with nandī (relishing/delight) and rāga (passion) is the origin of suffering. So if you were to ask someone understanding that if they relish mediation, they’d answer that they don’t relish opportunity to mediate neither meditation, nor the joy and happiness that come from meditation.
Thus one may think that there is no fun at all - but what is the definition of fun, or is there a need for fun if there is peace, joy, happiness.
A prisoner may get bored at a fellow inmate who decides to work on his swift release rather than trading mobile phones and drugs.
Likewise, an engaged member of society may get bored with a Buddhist on the path to enlightenment.
I think it depends on why the person is asking. If they are just being snarky, there’s really no point in answering. If they are interested in Buddhism, but are struggling with Buddhist practice and/or ideas, I guess I would ask follow-up questions to identify what they are looking for with their question. Is there anyway I could help.
Another approach. In the 1980’s, when I lived in NYC, I was at a talk given by the Zen teacher Seungsahn. One of the students asked him:
“Isn’t meditation boring?”
Seungsahn yelled, “Attain boring.”
So you could always say, “Attain no fun!”
How would you counter the observation that Buddhists “do nothing” all day?
Hard to explain what happens on the cushion.
But usually in counting breathing or following breathing, you feel as if you are doing something, you know– you are following breathing, and you are counting breathing. This is, you know, why counting breathing or following breathing practice is, you know, for us it is some preparation– preparatory practice for shikantaza because for most people it is rather difficult to sit, you know, just to sit.
(Shunryu Suzuki, “The Background of Shikantaza”; San Francisco, February 22, 1970)
“Just sitting”/“shikantaza” is ceasing habitual and volitive activity of the body while conscious of the body, ceasing “doing something” with regard to sitting while yet conscious of the activity of inhalation and exhalation. I believe that’s the experience Gautama ascribed to the fourth jhana, where activity takes place solely by virtue of the free location of consciousness (in Gautama’s description, with the experience of “purity by the pureness of (one’s) mind”, MN III 119).
As Suzuki said, for most people such experience is difficult to find, but I think a better explanation of what the experience is could go a long way to preparing the ground.
Of course, that’s not the same as ceasing habitual and volitive activity of the mind while conscious of the mind (something I can’t say I’ve experienced).
When one investigates the Dhamma with clear comprehension, they relish every opportunity to meditate. Seeing the results of this practice…
“Seeing the results of this practice”–for me, seeing results can be counterproductive. More like:
So, when you practice zazen, your mind should be concentrated in your breathing and this kind of activity is the fundamental activity of the universal being. If so, how you should use your mind is quite clear. Without this experience, or this practice, it is impossible to attain the absolute freedom.
(“Thursday Morning Lectures”, November 4th 1965, Los Altos; emphasis added)
“How you should use your mind is quite clear”, a relief.
“Attain the absolute freedom…”:
And what is the cessation of deeds?
When you experience freedom due to the cessation of deeds by body, speech, and mind.(SN 35.145, tr Sujato)
I actually prefer the Pali Text Society translation:
And what… is the ceasing of action? That ceasing of action by body, speech, and mind, by which one contacts freedom,–that is called ‘the ceasing of action’.
(SN IV text iv,129, XXXV, III, 5, section 145; © Pali Text Society Vol IV p 85)
Your last question:
… how (do) you maintain a mind that is free from hindrances, and/or make meaningful an impermanent worldly activity?
For me:
I sit down first thing in the morning and last thing at night, and I look to experience the activity of the body solely by virtue of the free location of consciousness. As a matter of daily life, just to touch on such experience as occasion demands—for me, that’s enough.
I would argue that Gautama attained the fourth jhana regularly, and touched on it in “the contemplation of cessation, breathing in and breathing out” that was a part of the mindfulness that made up his way of living.
From DN 29:
Cunda, these four kinds of indulgence in pleasure lead solely to disillusionment, dispassion, cessation, peace, insight, awakening, and extinguishment. What four?
[The four jhanas] […]
It’s possible that wanderers of other religions might say, ‘The ascetics who follow the Sakyan live indulging in pleasure in these four ways.’ They should be told, ‘Exactly so!’ It’s right to say that about you; it doesn’t misrepresent you with an untruth.
It’s possible that wanderers of other religions might say, ‘How many fruits and benefits may be expected by those who live indulging in pleasure in these four ways?’ You should say to them, ‘Four benefits may be expected by those who live indulging in pleasure in these four ways. What four?
[Stream wining, once return, non-return, full awakening]
Maybe this translation of DN29 could be improved?
It calls sukhallikānuyogā “indulgence in pleasure”
anuyoga
- masc. praxis (of); practice (of); devotion (to); pursuit (of); doing (of); lit. yoking alongside [anu + √yuj + *e + a]
- masc. scrutiny; examination; enquiry; lit. yoking alongside [anu + √yuj + *e + a]
- masc. corollary [anu + √yuj]
The problem arises when compared to MN138:
When there is vivekajapītisukhānusāri viññāṇaṁ (viññāṇaṁ that follows after that rapture and bliss born of seclusion) —tied, attached, and fettered to gratification in that rapture and bliss born of seclusion—the citta is said to be stuck internally.
Anusāra
- “going along with”, following, conformity.
So from DN29 we find that anuyoga is okay, but from MN138 that anusāra is not. Now what remains is to understand and realize which one is which. I wonder, could someone differentiate these two concepts in greater detail or provide their feedback.
Although it may look a lot like doing nothing, they are meditating. I think this is the most difficult thing to do.
Imagine sitting at a crossroad and contemplate on emptiness. Unless you are a seasoned meditator, you are likely to go mad.
With Metta
Doing nothing is our ultimate goal should we say which is total cessation ?! 
Would you say an outsider going hiking up a mountain (which is just an act of walking) or sitting at seaside simply gazing at the sea enjoying fresh cool breeze or didn’t do much merely sun bathing (which is but sitting and lying down) that too is but doing nothing ? 
Both terms are neutral in themselves and can be conjoined with both good and bad things.
Anuyoga is from the verb anuyuñjati (to practise, to give oneself over to) and means that the thing with which it’s conjoined is regularly engaged (or indulged) in.
Good 'uns
jāgariyānuyoga - devotion to wakefulness (i.e., making it a regular practice to get by on minimal sleep).
bhāvanānuyoga - devotion to cultivation.
samathānuyoga - regularly applying oneself to the development of calm.
vipassanānuyoga - regularly applying oneself to the development of insight.
Bad 'uns
surāmerayamajjappamādaṭṭhānānuyoga - regular indulgence in intoxicants.
vikālavisikhācariyānuyoga - regularly roaming the streets at nights.
jūtappamādaṭṭhānānuyoga - indulgence in gambling.
pāpamittānuyoga - regularly consorting with bad friends.
ālasyānuyoga - habitual laziness.
As for anusāra and anusārī, these will have to wait for another day, unless someone else wants to deal with them first.
Good question! Let me tell a story.
Years ago I was in Bodhgaya, near the Ashoka pillar by the lake. There’s a little courtyard there, and in one corner, a group of German pilgrims were sitting, very seriously and devotedly reciting a Tibetan text of some sort.
Now, the pillar itself is broken, so the top is mostly flat. And around it were playing a bunch of young Tibetan novices, ostensibly dedicated reununciates. They were challenging each other to throw a coin up on top of the pillar, to see if they could get it to stay there without falling down. They were laughing, teasing each other, celebrating wins.
And I saw these two groups, one so stiff and proper, the other so happy and joyful, and I wondered: which is closer to Nibbana?
Could be the neither quality lends itself or detracts from being spiritual.
To answer in an oblique fashion, I’d like to point out that there are two types of vacations.
One is the vacation which is crammed with activities from morning to night, replete with deadlines, travel to distant places, sightseeing, exploration etc.
Another is the vacation where there is nothing at all to be achieved and nothing to get done. Its simply a switching off, a letting be… lazing by the pool or maybe even in one’s own house.
The large majority of people enjoy the former, and cannot think of any good reason why anyone should waste that that valuable vacation time - doing nothing?
A small minority enjoy the latter, because they see value in getting off the treadmill once in a while. They cannot fathom why anyone would willingly burn themselves out by going on a vacation that leaves them even more tired than before.
Both look at each other wondering ‘How can that be fun?’ 
I would try to gently and thoroughly explain that meditation is an active process that involves abandoning the unwholesome, cultivating the wholesome, and purifying the mind. Perhaps I’d use the example of an exercise they could do where they sit quietly by themselves without distractions so they can see for themselves that far from doing nothing, their mind is in fact always doing something. The beauty is that anyone can verify this experientially, they don’t need to have certain beliefs. The Dhamma is well expounded by the Blessed One, apparent here and now, timeless, encouraging investigation, leading inwards, to be experienced individually by the wise.