Why do people price games without doing market research?

And by market research I mean literally just checking Amazon/Target/Best Buy etc. for what current msrp is. I’ve seen so many listings online where people try to sell USED games/consoles/accessories for equal to or MORE than what it costs new.

Examples:

-used RDR2 for $50 when new is regularly available for $20 (I actually messaged the guy about this and his response was “ok” and still didn’t change the price)

-used and new Steam Decks LCD 512gb for $600 when new is $550

-used dualsense controller for $60-70 when new is the same

Even for items that I have no interest in or already own, seeing this makes me so mad lol. Are these people either a) basing the asking price off of what they paid for, months/years ago? Or b) not bothering to do 30 seconds of research to make their listing more competitive? Either way, they’re idiots.