Why does it cost so much to race?

I would really like to race at the track this summer but the cost is just so high that it's making me think twice. By my calculations the total for me to race this summer would come to something like $310 excluding the championships and trophy races, and not to mention the cost of gas for me to drive the hour to northbrook every week. For some adults who have well paying jobs this cost might be negligible however; I'm a 19 year old student trying to pay for college and I just don't have much spare cash laying around.

I really look forward getting out of school and coming back home to start racing; how ever it might simply cost to much.

I welcome any suggestions or comments.

-Thanks, dweider