You are guided by faith, not data. You wore a helmet when you crashed, and you lived. You also wore socks and underwear.
EDIT: I realize that there is no debate, as I will "never convince (you) they're a bad idea." I'm talking to the people who are coming at this with an open mind.
The only time I've ever crashed on bicycle was the one time I wore a helmet. I have stopped wearing a helmet because of the same 'logic'. I use my bike to get to work.
One minute from now, someone is going to hit you in the head. You have the choice of whether to put on a helmet first, or not. Which would you choose? Thus the benefit of wearing a helmet is demonstrated.
EDIT: I realize that there is no debate, as I will "never convince (you) they're a bad idea." I'm talking to the people who are coming at this with an open mind.