I've seen this appalling dichotomy in the plank world, where everything from crew ability assessed on a check, FTL's and maintenance are accepted at a lower level just because you have boxes in the back. (Or horses at a mill a pop?)
It was summed up some years ago by a union rep when questioned by a local politician as to why he was insisting on the same FTL's for freight as for passengers. His priceless answer was, "So when a 747 crashes into your apartment building, it doesn't matter to you whether it is a passenger or freight aircraft?"
The silly bitch backed down, and we got similar rules for both.