Nonsense!
This is a complete pile of rubbish, as well you know! And you, as a trader have a responsibility to ensure that your supplier provides you with genuine, fit-for-puprose goods! In addition, this completely invalidates any warranty.
It's like going into Curry's to buy a washing machine......you pay for the product, it arrives at your house but it doesn't come with a serial number or manufacturer's papers?
Where do you buy your products? From the guy around the back of the pub with the dirty white Transit van?
I wonder what Trading Standards would make of your claims? You are on a very sticky wicket here.......