I've had this discussion before with one of my good friends from high school, actually. My school requires a certain amount of community service before you can graduate. If you don't finish it, you don't graduate until you do. My friend always hated this; she wanted everyone to be altruistic because they wanted to be, not because they were forced to be. I used to argue with her because in the end, the people you're volunteering for don't care why you're serving them food or tutoring them or doing whatever, all they care is that you did it.