It's a fair question, but it's a bit like asking why people run in the New York Marathon. I mean, you want to run 26.2 miles...the road starts at your door. If you need to know how fast you went, you've got a watch. And if you need to run with people you could surely find some. So why go through the hassle of getting to Staten Island, waiting in line, etc. -- particularly when you have to pay for the privilege?

Well, because it's more fun that way -- something about participating in a big event is entertaining in a way that just getting up and going for a jog isn't.