Racism/discrimination

So a few weeks ago, a buddy of mine who works at another store across state deals with random customers being racist/discriminate towards them. They don't know what to do and it started 2 months ago and happens a few times every 2-3 weeks. Their SM has done nothing other than just telling them to walk away and ignore them, and have someone run the register till they can calm down. I wish I can do something if I were there but it's across state and I don't want to drive there as they live 3-4 hours away.

The worse that happened to them was that they had a mental breakdown cause there was an older lady who called them "Chinese" and yelling at them along the lines of "Go back to China or go on your knees and kiss my shoe cause this is America". Yeah, I would've told her to tell her to leave the store immediately for discrimination and have her ban at that store. I don't want to see my friend go down a path I wish to not see them go in.

What can they do next time someone calls them "Chinese" or discriminates them? Have the customer leave? My friend is Taiwanese and they hate being called "Chinese" when in fact, they're not.