Me (opening the driver-side, rear door of the cab): "After you m'lady."
M.O.M. (getting in and sliding over in the rear seat): "Gee thanks."
Me (getting in, telling the driver our destination, and then turning to her): "What? What did I do wrong?"
M.O.M.: "I had to slide all the way over to this side. If you wanted to be a gentlemen, you would have opened the door, closed it, and walked around to the other side and gotten in."
Me (after a few seconds of silence): "But I didn't want to do all of that. That seems like a lot of work."
M.O.M. (sighing): "How nice."