The main practice, very practically, is that we are giving up control and choice, and learning to be content with what is offered.
I think this is what might seem so jarring about seeing a monastic alone at a resto, even if the gift card s/he has used to acquire that meal is technically legal or not.
The precepts are a training rather than ‘rules;’ and sometimes modern circumstances make that training pretty complicated. We do the best we can…and long-distance travel and airports are especially fraught.
So I find myself nodding in agreement with you, Bhante, when you say:
For those of us who travel without kappiya, this is only a blessing.
When someone gives me a gift card that I can use it in transit after an all night flight, I am always grateful for the intended sustenance. The donor could not join me but wises to make sure a meal is offered anyway.
It does feel weird - but to be honest it’s more because of the choice than the card itself.