way that I think it’s inappropriate I can refuse to seat them. Bad dresser is not a protected class. If someone comes to my restaurant and stinks to high heaven, I can refuse to seat them. Smelly people are not a protected class. If someone comes to my restaurant, who I know routinely publicly and privately expresses hatred towards people who work for me who ARE protected classes, I think I should be able to refuse service. People whose politics express bigotry and hate are welcome to do so but they are not protected classes and are not protected from being unwelcome in my home or my business.
Where it can get awkward is where such people are individually in a protected class. In those cases, the home or business owner has to be able to clearly distinguish the reason the person is unwelcome.