I love playing with the button on the gear selector when I'm driving an automatic. It has a nice springy feel to it. I can completely imagine pressing that button many many times and then shifting from Drive to Park. If that activates some weird car mode, it seems kind of scary to me.
What I cannot understand at all, however, is why some important functionality is activated by some esoteric feature as this, in a car with a 200 square inch touch screen. Seems like this should be a menu option of some kind, in which the vehicle operator is able to clearly describe his intentions, with no room for ambiguity. "Want to turn on the feature that lets the car drive without you in it? Yes or no? Are you sure?" Doesn't seem hard. If they want to couple that with some actuation of "driver only" features like the gear selector, to reduce ambiguity over whether or not the driver actually wanted to enable this mode, all the better.