If I were born 15 years earlier I probably would dislike the Brewers some. But I wasn't, so I just hate on the Yankees instead because they keep knocking my Twins out of the playoffs. >:( Though I don't even despise any of the individual players, just the organization itself. I don't really hate any team all that much.
I was a Packer fan initially in life. I did it because my dad's and my uncles's reactions were funny to me at the time. XD
I came to my senses later, though, and started supporting the Vikings, though I don't despise the Packers unless they're playing the Vikings at the time.
Doesn't mean you have to ditch your interest in sports, Sammy. Look at me, for example. I really like sports, yet I'm also really into video games and manga and such!