The money trucks always park in a location that makes it hard for robbers to block them in, and easy for the person carrying the money bags to have a clear, simple path between the truck and store. Yes it can sometimes seem like they're being jerks, but it's for their own safety. And having dealt with them as a store manager myself, they're a very no nonsense bunch, but they're also quick and efficient - in and out as fast as possible. If you don't have your money drop ready when they get there, they leave without the money.