[MunchkinMan]

The use of "trade" in Banana Boat is probably trying to make sure that it's clear that the two Ships must change ownership, but "swap" would be an equally correct word.

In any case, if your friend was correct, then all trading could be executed on an unwilling player. That would turn Munchkin into a game where everyone just takes everyone else's in play Items all day long, and, well, that doesn't sound fun to me.