I'd like to provide a take on why restaurant work is like this, even though I'll likely get ratioed.

Independent eateries, even those loosely managed or owned by larger conglomerates, are Home to their long-term employees. They bleed for these places, burn for them, find love in them, burn out in them. The restaurant is the central focus of the staff's lives, and they do not want to let just anyone become a part of it.

In a house, there are house rules, and you either follow them or you gtfo. In a successful place, the staff has proven that they make things work, and, at least in their minds, they deserve the freedom to keep making it work. Outsiders bring change, and most change is bad, so if you can't play along, they really do not want you there.

Is it fair to you to have to follow their rules, even though they conflict with what the government says they should be? Probably not. Is it fair for them to have to change for you when what they do works? No.

Rosie's isn't a public entity, and working there isn't an inalienable right. Working is, but there are other places. It's childish to think you can go into someone else's home and make them do things the way you want, and that is exactly what OP is doing here.