I used to be a huge fan of Jon Favreau, but a few years ago he made a homophobic “joke” in an interview (on TV). It wouldn’t have been so bad if he’d just apologized or said that he misspoke or something, but instead he got defensive about it (on the Dinner for Five message board). I’m still a fan, but I can’t watch D45 episodes the same way anymore. 
(A bunch of people on that board got very weird about the whole thing . . . I haven’t been there since.)
While I agree the WAY she went off on fan fic authors was over the top, technically, she was in the right-she doesn’t have to allow fan fic if she doesn’t want to. Most authors just ignore it, but some have had bad experiences (Marion Zimmer Bradley had to shelve a long-awaited novel in a series because she was sued by a fan fic author who claimed plagarism).
The Amazon reviewing-oy, was that bad. Talking about her “proletarian soul” and how her “dickensian principals were stretched to the maxx,” or something like that.
She gave her address and told people if they wanted a refund, to send her the book and she’d give it to them-and she swore she was serious.
Those who took her at her word had their books returned to them, unopened marked, “Return to Sender”. It turns out the address she had given was that of the house she had recently sold.
I didn’t know he was a Republican, but I heard him speak once at a Planetary Society meeting and boy, what a pantload. He got beaten up one too many times on the playground.
I was unable to respect Allen Ginsberg due to his affiliation with NAMBLA.
While I’m not a huge fan of John Wayne movies to begin with (except the ones with Maureen O’Hara), reading his Playboy Interview was jaw dropping. (He didn’t think blacks or women should be allowed to vote- and this was in the late 1960s!)
I’d always thought of Bill Maher as an egomaniacal but harmless TV talking head (I didn’t like him), but when he began telling audience members not to innoculate their children (and even working it into his standup) I thought he crossed a line.