Amazingly about 15 minutes after I posted that last story about why video game violence exists, I read this story on digg's front page.
Basically a family's Jeep Grand Cherokee swerved off the road and rolled over a few times before resting on it's back. The 11 year old child who'd presumably been illegally playing Grand Theft Auto beforehand realised cars blow up in-game when they are upside down and that provided the much needed motivation for her to help her family to get the hell out!
Indeed, GTA IV is slightly different as the cars no longer blow up when upside down - however you do get a 30 point xbox achievement for rolling your car over 5 times from a single crash. An achievement they narrowly missed by rolling over only 4.
There is no word if the girl later car-jacked another motorist to take her family bowling.