I do not trust you, because I have been a food service worker and actually know what I'm talking about. A customer expressing a preference has never bothered me if they weren't rude about it. If it happens often enough it does get passed on, even though the individual impact of any counter conversation is low. You are trying to turn normal amicable commercial interactions into some kind of moral purity test.
> I have been a food service worker and actually know what I'm talking about.
Same here.
> A customer expressing a preference has never bothered me if they weren't rude about it.
A lot of people are seemingly skipping over OP describing their behavior as creating a “hostile atmosphere”. That is inherently rude.
> If it happens often enough it does get passed on
But we aren’t talking about just telling your manager. There are so many layers of management and bureaucracy with larger corporations, especially ones with a structure like McDonalds’ franchise model, that these complaints will not make it to the decision makers.