buying anything on a secondary "used" market is and has always been buyer beware. It is up to the buyer to make sure they are getting what they are expecting and are cognizant of the underlying costs. Any misrepresentation by the seller is not cool and sellers that act this way don't survive long before people no-longer buy from them, and in this case I feel bad for anyone that did their homework and simply didn't receive what they intended to buy through no fault of their own (ripped off). On the other hand, if someone a seller prices something above market it is the buyers responsibility to recognize this and through the powers of supply and demand simply make that calculation for themselves, if you buy something and then come to find out you overpaid (and allow this to impact you emotionally), perhaps you shouldn't have bought it in the first place.
If you buy something that you want, got exactly what you ordered, just could have bought it somewhere else cheaper, better to just let it go and enjoy what you bought because at the time you bought it you were okay with both the item described, and the price and got exactly what you paid for.