That suck and I bet they ahve no balls as the car wont hit back.
I heared a really good story like this on the radio a while ago. A guy had a quite expensive Mercedes Benz parked in a car park. While walking back to his car he saw a guy keying his Mercedes Benz. He walked up to him and said to the guy keying the Mercedes Benz "That's not how you do it, let me show you how its done". So he grabbed the keyer by the back of the head and proceeded to smash his head/face against the panels he keyed. A very valuable lesson was learnt.