They would rather back into a parking spot surrounded by stationary obstacles than back into a parking lot or road which may contain pedestrians or other drivers.
I'm not saying _I_ back into spaces. I generally drive into spots and reverse out of them. However, I admit that what I do is a tradeoff where I take on risk in order to have a mechanically easier time entering and exiting the space.
This makes no sense. In either case the car traverses the same space once forwards and once backwards.