I have seen the same thing. No Chocks and the front elevators blocked up on cinder blocks. Guy backs into the hitch...trailer rolls back...falls off of blocks...crunches bed rails on brand new Ram dually. Thing is...about 10 of his friends are standing around helping him get all lined up. Nobody thought of chocks?
Then they were all kibitzing about how to get the trailer off the bed for re-hitching. I offered help, and two jacks. I was told to mind my own business. "Charlie has been towing for more than 30 years. He knows what he is doing. Doesn't need any help from you."
I no longer felt any compassion for the guy. He deserved what he got. Seems he'd been doing it wrong for 30 years. Maybe he learned? No chocks is bad. Blocking the front struts is bad. Cinder Blocks is bad and just dumb. I hope I am not around when he rolls out of bed when his cinder blocks crumble.