And some idiots would rather be "thrown clear" of a crash (into a tree, or oncoming traffic, for example), so they don't wear their seatbelts. Darwin referred to this as natural selection.

Most people want their doors locked for security purposes (i.e. so no can get in easily while you are stopped at a traffic light, etc.). They also provide security against the doors coming open in a collison, which is almost never a desirable thing (ask any police officer).

I, for one, don't consider auto-locking foolish because I *always* want to drive with the doors locked and sometimes I forget to lock them. This is compounded by the poor ergonomics of the XC locking system which uses a toggle, rather than having separate "lock" and "unlock" buttons. You must take your eyes off the road to see what state the doors are in before using the lock button. And if one door is unlocked and the others are locked, the system gets totally baffled. I just tell passengers to pull up the lock knob if they want to get out, because I cannot guarantee that I can unlock their door with the control. Many times I've used the keyfob to reliably unock or lock the car from the inside, because it wisely provides separate lock and unlock buttons.