The trader is selling these diamond items because Lilith wants you to accidentally buy it.... It's a trap! Who would buy these items otherwise?! People always complaining about accidents like this but Lilith can't even sell these item on the other side of the shop like how they are selling soulstones and items in other shops.
Nope, but some people didn't check carefully if that was Diamond Pic or Gold Pic (Simple, but always ignored)
Another that most of them ignored is the pattern of the icon (It's either in fragments or Item) cuz that kind of detail somehow make wrong click.