This reminds me of when I stopped for a snapping turtle. Except that I put my car in park, removed the keys, set the parking brake, and turned on the flashers. I expect a situation like that would take a few minutes (which mine did).
I would have been amused if some kid hopped into my car unarmed with the intention of driving away. I'm 6'2", a muscular 230 lbs, and can run relatively quick. I would likely make him soil himself. Then again, when criminals look for victims, they usually don't pick people that look like me.