Whaaaaaat!?!? I'm so sorry to hear that. I would've stalked every local sale for the next few months until I found the ****er and slit his throat.
On topic, I love setting up and selling but I can't stand the usual crowd that Garage Sales bring. It's the cheapskates and derelicts. People are savage and ruthless and have no regard for the people who are selling. I've had people tell me off because I won't lower a price. I had one guy ring my doorbell at 6am. Then again I've met some really nice people as well. Those are the people that I give stuff away to and they appreciate it.