I remember @quuador said he purchased multiple of those bleached cards from that seller before - www.elitefourum.com/t/uv-testing-according-to-a-scientist/21208/1
Really neat effect and shows what extreme UV damage can do. For $5 dollars a piece and an accurate description, the seller is not trying to scam anyone. It would be strange to collect these or even think of selling them in the first place, but if someone enjoys them, then why not. At least they aren’t fake cards.