I suspect that "overloading" happens fairly frequently; overloaded to the degree in the picture, probably not too often.
Prominent local lumberyard won't load for non-account customers (they will put the lumber on the forklift at truck height for the customer to manhandle).
The account holders, when signing up, have to execute a very strong liability release that, in part, says "...loading only done upon customer request and per customer direction...".