Seen a few of these "Lucky Bags" at a car boot today, pointed out to my son that if they were good the stall holder would have opened them and sold the stuff instead of just leaving it sealed.
About 11 years ago we spent £250 on an Argos return pallet what a waste of money we had 3 vacuums , one worked, 5 microwaves one worked, and various other things of no real value, we landed up selling the whole lot to some guy for about £90. He had the trouble of getting rid of the broken crap.
Im a postie and some of the crap that gets sent to random addresses is insane , the small grey bags from china are the worst , they might only have a coathanger or paperclips in them.
Rather than "Royal Mail" returns are these returns from said companies sold off to a third party that sells them to you? Probably cheaper for the "Clevia" or whatever they are called to do that than check everything and restock it?