I think for most people it does. Unless you grew up in a really cynical household, it's pretty normal to idolize sports "heroes" when you're a kid. Kids don't think about the financial aspect of the game, or the flaws of their heroes, or whether society prioritizes sports too much. Then you grow up, and you see the larger picture.
Then, there's the practical aspect. As an adult -- especially if you're working, married, and raising kids -- it's almost impossible to be a diehard of four pro teams. When I was a kid, I tried to catch as many basketball, baseball, football and hockey games as possible. It was routine that I'd catch at least parts of 150+ baseball games per year. Now, I follow the Bruins and Sox (and Chicago Bears), but the Celts are the only team I'm a diehard with.
But, I have found that I get just as excited for the games as I used to. Winning never gets old.