Parking Wars

Today we went to the pharmacy to pick up Bob's meds. Right after we pulled into a parking space a woman pulled in next to us on Bobs side. He immediately  started chastising the woman for parking on the sidewalk. I said "Bob-- stop- she is NOT on the sidewalk. This is a parking lot." To which Bob replied " I know its a parking lot. Thats why she should use it.
HUH?  ( and he still doesnt understand why he no longer has keys to the Jeep.)