I got my love of sports from my father. He played college football and was a huge Dolphins fan (I grew up in South Florida), and through that I became a huge fan of every South Florida sports team. He was a workaholic so spending the day with him at a Dolphins game was something I lived for as a kid. Since I am 35 most of the South Florida sports teams, like the Marlins, Heat, and Panthers, only came around in the last 15 or so years so I watched them from their infancy, and went to many of their first games.
I also played every sport, but I was especially good at baseball. Back then the college recruiting rules were that schools couldn't contact you directly until your junior year in high school, but they could send you what was called an "introductory letter", which was a letter telling you about the merits of the college. In actuality it was a backhanded way of saying the school was interested in you. I got several of those letters after my sophomore year. Unfortunately, by that point I had grown my hair down to my ass, and was more interested in being in bands than I was in playing high school sports. I ended up quitting part way though my junior year.
I went to college at the University of Miami, and although I didn't play sports there, I still follow their sports teams fanatically. Unless you have gone to a college with a football team, you have no idea what it feels like to sit in the stands in the student section, cheering on your team and doing all of their traditional chants.
So to make a long story short, it is pretty easy to become fanatical for your home team when you grew up around them and they were such a special part of your life. Oh, and I wear my Dolphins and marlins jerseys all the time, and anyone who doesn't like it can blow me
