You do a good job of describing the phenomena that is "being a fan"! Although I'm not a huge sports fan myself I "get it". I believe rooting for your team and the camaraderie amongst fans fulfills us on a primitive and intellectual level. I've known people who live, eat, and breathe sports and was always amazed by how it affected every aspect of their lives. I had a friend whose entire week was shot if the Vikings lost on Sunday. Unfortunately, that happened quite often. : ) Baseball, by far, is my favorite sport and the hotdogs ARE amazing...I agree with Bogie too.
It is definitely primal! It can take over someone's life and totally affect their mood.