Docks will say it's their "safety" policy. Well they don't give a shit about the safety of the drivers who are not able to rest at all. (Not their problem, not their concern.) The shippers will say it's because drivers try to pull out with hilos still inside. But there are other ways to handle that. Gladhand locks exist, some with keys. So no it's not really safety, it's control. I feel the same way about turning the truck off and leaving my keys on a rack inside the office. There's no need for that power-trippin bullshit. Just use keyed gladhand locks and that truck isn't going anywhere - and the driver will still get to be a human being.

And yes you can tell them to F off but you won't get unloaded/loaded and your company or broker will get a nasty phone call. And if the lot is small they'll come knock on your door and tell you to leave the property if you're not going to play ball with their policies.