I thought the van might have stopped so the driver could adjust the gps, or answer a call. When I was on the school bus run in Sydney (it was a small 11 seater bus) we would pull over for those types of things, or to check the schedule. Unless a van has "free candy" written down the side, and the van driver is leering at you then I think you're pretty safe (especially in the middle of the day and in a nice neighbourhood).