I wonder if he complains when the blacks (notoriously poor tipers) stiff him on his tip?
As someone who spent some time waiting tables in his youth, I can confirm (anecdotally, but the consistency was remarkable), that this is absolutely true. But beyond that, they also often seemed to go out of their way to be the most demanding, difficult, inconsiderate, and condescending customers, by far. They were so consistently miserable that even black waiters and waitresses didn't want anything to do with them.