Probably just trying to keep on schedule. That reminds me of a story. About a year ago, I was filling up at the diesel pump when I noticed the delivery van at the opposite pump rolling away with the nozzle still attached. I ran over and found no driver, so I jumped in and put on the brakes before it crashed into some new ricer. Funny thing was that the auto tranny in this thing did not have "Park." Apparently the driver had gone into the store without setting the e-brake.