Some of us though can't afford two bikes. I can't afford to commute on a beater bike, it just takes too long. I have ONE nice bike that I commute one and race on (road and cyclocross). It's a $2K bike but I park it at bike racks in very public places near entrances to work/class, lock it with two seperate lock types, and walk by it every couple hours at least. It's all I can do but I can't afford to go on a cheaper slower bike.