Do they violate "free association" by refusing to let people sit at their lunch counters?
No, they violate anti-discrimination laws.
Good question.
Many bars have signs saying ‘We reserve the right to refuse service yada, yada, yada” So why not lunch counters?
If patrons come into a restaurant and become unruly, would this apply? I’ve taken high schooler after an event to eating establishments and been asked to leave. I’ve seen bad behavior from minorities and they cry ‘Racism’ when management treats them the same. Because we are wasps there is no recourse?
I don’t have that answer.