Hehehehe... I hope this doesn't turn into another "Which team started it" like the whole Heeeeyyy thing turned into.
Anyways, as for my team we saw it on a car's bumper sticker and just added the word robot to it.
Then a few years back, I think it was Matt Leese (maybe) that was making some FIRST inspired T-Shirts with funny and cool bot related quotes on it, and he asked me if he could use that slogan "Drive your robot like you stole it" cause it was in my signature at the time.
I said sure, and he had some shirts made up with that slogan on it through
edit: geek-gear.com and I bought one of the shirts. I still have it to this day.
Anyways, the whole "drive it like you stole it" is basically saying, go ahead and drive aggressively. Maybe not the most gracious or professional slogan ever, but.. meh. As long as you got a good pit crew, go ahead and drive it to the extremes - just be ready to fix it after a match.
