Always loved this track and video.
I read somewhere that the song is about someone Thom knew who couldn't keep any friends b/c he was a douche. "You do it to yourself, you do"
Basically I thought that the basic message is that everyone is responsible for their own actions.
The dude is all depressed and shit and wants to be left alone. But he lays on the curb and attracts unnecessary attention. "You do it to yourself".
Also the crowd keeps on insisting for him to tell them why he's lying down. He keeps on resisting and tells them what he may say will make them want to lie on the curb. But they keep on pressuring him, and when he finally tells them, they all lie on the curb. They did it to themselves.
It really doesn't matter what he said in the end.