Dunno why but I get the creepy feeling that rampant, soulless, pointless, hopeless liberalism at these 'elite' univs has something to do with this self-abuse thingie....
Would you believe I have a niece in college, who is strongly right wing, raised by a conservative family, who have just found out she's been cutting herself. Its true.
I would associate it with the stress level, pure and simple. In earlier, simpler times the stress level was generally lower, and/or the people had better coping skills. Given enough stress, everyone would snap.