There are quite a few of those mentioned that put me off too. I am not sure where the line is between that and "ick" but I do feel there is one.
Gerard Butler does give me the ick, he just seems to be in love with himself. In kind of a weird creepy way.
Brad Pitt, on the other hand, I don't find attractive at all, even though a lot of people do, but I'd not say he gives me the ick.
Owen Wilson, there is something wrong with his mouth and it creeps me out a lot.
DiCaprio, I don't get the ick, but I keep thinking how can anyone have a head so much like a pumpkin, so it's a distraction to watch him in anything.
One thing that strikes me, there are some mentioned that I find inexplicably compelling and attractive. Brian Cox, even as a young teenager watching Sharpe, and Hoffman. I wonder if there is a fine line between what makes someone not conventionally beautiful seem so compelling to some, and icky to others?