You can’t scam people within the confines of the rules and without lying.
Who cares? Intent doesn’t matter and the Blizzard post said exactly as much. You can’t infer intent from just an AH posting and so unless that poster tells you openly they want to defraud you (which defeats the purpose entirely) you literally cannot separate bad actors from good.
If your opinion is that only people who are bad do these things, that’s just you being a silly person.