I didn't grow up in a sporty family, so I never really got to experience professional sports until I was in grade school. I watched Boston beat Miami when Pierce hit that buzzer beater (2010 first round), and I've been a fan of the NBA ever since.
I make a concerted effort to watch other sports, though. I make sure I watch the Superbowl, World Series, and NHL Finals, just so I know a little bit when I talk to my friends about those sports. But I really just enjoy the NBA and college basketball and football. That being said, my friends love the NFL, for the same reason as you do. Every game is a great game, they tell me.