Why do so many people care what "celebrities" are up to?

http://www.gocomics.com/nonsequitur/2013/04/04

I guess that's what makes them celebrities.  The people who don't have much of a life of their own, live through the lives of others.  Too bad all the attention makes the celebrity life fail.

I guess they are the modern form of the Greek Tragedy.

Being the non-conformist, I also have trouble understanding fan mentality.  Ya, I route for the Yankees, if I happen to be watching a game.  But I am nowhere near a fanaddict.