Originally posted by Forsaken1:

Your friend is a liar/cheater and is probably using valheim+ mod. You can set your carry weight to whatever you want and increase gathering ratios. You can change just about anything you want to edit. I would definitely not play with that "friend" if he cannot be honest.

He keeps insisting it must be a glitch because he hasn't installed any mods. Is it possible that he was on a modded server at some point, and it auto downloaded some files?