For me personally, Tom Cruise is the only actor that I refuse to give one dime to because of his personal beliefs. I find Scientology to be one of the vilest cults in existence. When I found out they sued the Cult Awareness Network into bankruptcy, than bought it, that was enough for me. Think about it: If someone calls the Cult Awareness Network looking for support in leaving the CoS, their call is answered by a Scientologist! I will never knowingly give money to a member of that group.
That isn't to say that I won't watch a movie with that freak in it. That's what Bittorrent is for.