When in Hell One, if you and someone else go to a pile of grapes and you hold down the return/enter key to get the grapes smashed before the other player, you can end up giving the other player some of your inventory if you aren't paying attention and keep the key pressed too long. It's no big deal if it's meat in your first slot as that goes to the other player 1 meat at a time, but something expensive would be bad. I end up accidently friending people, too. If the default menu choice on another player could be "never mind" in Hell One, that'd solve it. Not holding down the return/enter key also works. :-)
This may good everywhere in-game, like if I'm petting a pig by keeping their return/enter key pressed and someone walks up to me as the pig leaves. Haven't tested it.