I suspect that some will argue that there are no “standards” for behaviour in public, only cultural norms. And that to apply the norms for white middle class people for behaviour in public to those of other ethnic communities and/or socioeconomic groups is inherently discriminatory.
Not saying that I agree with that, but some will certainly argue that way. I would say that as a business the people operating this wine tour train are entitled to have their own standards for behaviour such that some guests aren’t disturbing the enjoyment of other guests. I seriously doubt if having paying customers, particularly black ones (everyone being mindful of racial matters), removed from the train is something that they enjoy having to do.
Standards are cultural norms. Which is why they are pushing against the cultural norms. Norms must be revised and whites must be made to submit.