Why are people so touchy about media likes and dislikes?

Is it so personal to have a favorite T.V. show? Or like certain music? To dis someones taste in music, movies etc. can be tough. Each to their own I think. Nothing wrong with ones opinion either. Why do people take that sort of thing personal? Not like they wrote the tunes or starred in the show. Is the likes and dislikes of certain media so entwined with the individual that it becomes personal? Why?