Originally Posted by J.C. Koto

At one point, so the urban legends tell us, this was a way to mark gang territory . Nowadays it still may be true, but I think kids mostly do it for fun when they get a new pair of shoes. Just one of those things that people see and decide to imitate. I've done it when I was a jerkwad idiot teenager...

As for the single shoe, I don't know either. What I want to know is what's up with all the underwear I see on the side of the road?