I realized, that Tiger wears a hat with his TW logo on Thursday and Friday. But on the weekend he always (at majors) wears a hat with a Nike logo on the front. Here you can see his apperal for the 2012 PGA CHAMPIONSHIP.
And here is the apperal for the 2012 masters.
It's always the same thing at the majors. But at normal PGA TOUR tournaments he doesn't do that. Why? Does anybody know that?