I wouldn't spend money on John Mayer anymore, but what about people like Matthew Gray Gubler, who says that Roman Polanski is one of his favorite directors?

It'd lessen my enjoyment of them, whether to the point of giving up the fannishness would depend. In this case of Roman Polanski, I don't think I'd feel comfortable fanning anyone who has looked into the rape case and after consideration given a clear "I like him anyway!" statement.

But yeah: it's a long list, and longer the less direct the dickishness is.