Guys, I think you're missing something here.
He's not saying ugly people SHOULD kill themselves, it's that there's a clear motive. God knows my self esteem took a hit when people called me ugly. Sometimes I wanted to shoot those people (shootings) while other times I just wanted to shoot myself (suicide). I could totally see it leading to other things as well.
On the other hand, beautiful people really shouldn't have to worry about being ugly so there's less of the aforementioned scenarios, which is ironic because a lot of the people on that wall were actually decent looking people. He's wondering why such people would want to kill themselves.
tl;dr: He's not saying ugly people SHOULD kill themselves, it's just that often they do. Trust me, I was there once when people called me ugly.