I once ordered 5 stools, and they delivered 25. It wasn't a scam, it was a genuine dispatching mistake on Amazon's part. I let them know, and their response was to just keep or "dispose" of the extra stools.
(I ended up donating them to a local piano teacher.)
Did you order 5 piano stools? I have 2 grand pianos, a clavichord, and about 30 electronic keyboards and I still only have 3 piano seats (1 bench, 1 stool, 1 drum throne). So now I have to know what you used those 5 stools for ;)
Second... how long did it take you to find 20 piano stool recipients? And how did you get the message across? Every time I try something like that I get treated like a scam artist and lose interest in helping.
(Incidentally, I do play piano, but the 5 stools I ordered weren't intended for piano use on my part, I was just using them for overflow seating for friend gatherings.)
I would do this, with the understanding that A) If it's illegal (drugs) or stolen goods, the police should come take it off your hands, and B) while the company in question may not be able to charge you, they might have other ways to "incentivize" you to return it.
E.g. if it's Amazon they might cancel your account and blacklist you. Depending on the value of the item (and how much use you can get out of it), it may be easier to return it than to not use Amazon if you do often, or if you use Prime and/or Prime video/music, or worst case, your name is the main one on the AWS account for your business.
I would gladly return some Google store pixel phone if it meant I didn't have to worry about my Gmail account being locked, and all the problems that would cause me (and yes, this is a good reason for me to have a different email).