^This. People get nervous around that which they don't understand.
I was mugged once, I was with a friend and she thought I was messing around. Yes, messing around with people I didn't know! They were would-be muggers though, they didn't get anything. They did force me down onto the ground though and I hurt my knee fairly badly. There were four of them I think. And they still couldn't get my wallet off me, heh.