Perhaps we can start a David Letterman style top ten reasons track bikes don't have brakes, only one gear and can't coast.
I'll start. Let's see, hmmm...okay
Track bikes don't have brakes because:
1. You can't get hit by a reckless cabbie or a soccer mom in her SUV on the velodrome.
2. you'll never hear "get off the velodrome" by the rednek in the pickup truck.
3. There are no stop signs or traffic lights in the velodrome so you don't have to wait for the little old lady to cross the 'drome. You also can't get a traffic ticket for blowing stop signs/lights on the velodrome.
Track bikes can't coast because:
1. You don't have to get out of your pedals to kick the loose dog that's chasing you on the 'drome (they also don't have water bottle cage bolts on the frame because you'll never have to squirt the dog with water on the velodrome).
Ok, that's all I can think of for now. I know, they sound dumb. Anybody got any better ones?