This is one reason that I enjoyed hauling coils. Rarely spent over 1-2 hours at any shipper or receiver. Usually much less time than that.
being at the mercy of someone who most likely hates their job and gets paid less than you is the worst feeling ever. you just know they have a chip on their shoulder and would love to show how little they care the moment you complain. best you can do is kill them with kindness or do something where you don't have to wait on others(LTL, Fuel, etc).
Unfortunately we have the problem in the LTL business too. The freight destruction that occurs on our dock is an absolute obscenity. You should see some of our loads in the morning.
I would get paid for every minute of that time, waiting free of charge is reason for the abuse drivers put up with