This sort of incident isn't very likely to happen, as you might have gathered. The thief only got in because a friend borrowing the 550i had left a key fob inside, and it's not very common that a thief is foolish enough to sleep inside a car shortly after the theft (especially with the engine on). Still, this shows how much riskier it is to swipe a car in the modern era. Even if crooks get past the initial security, they can easily be caught if they're known to be inside the vehicle. Let's just hope that hackers and less-than-upstanding authorities don't abuse this power.