I’m a white American who loves Chinese food (Japanese, too). Over the years, I have been to many Asian restaurants, yet I don’t recall having ever seen many black people in any of them. In fact, I’ve noticed very few. I’m curious about where you got this notion. I think I will have to start making an effort to take a (discreet) look at other restaurant patrons. Perhaps I will come back here and let you know what I learn.