Holiday Question

This is something that's always bothered me:

You know those car commercials they show this time of year, where they blindfold/cover the eyes/etc of someone and either bring them to the window or out into the driveway, and surprise them with a new car, complete with big honkin' bow around it?

My question is: How the heck do they bring the car there quietly and stealthily without the gift-receiver not noticing?