Everyone's seen this - a party reaches an elevator and one guy goes up without ditching their Vitapod, vials and pills. In my experience it's usually just people being forgetful, or not knowing how to drop their items, but some people get really upset about it, and it is kind of rude, and inconvenient to the remaining party members.
So, my suggestion is simple - have the game automatically dump this stuff outside the elevator on the next level.
It is acceptable, but also abusable.
Kick player, steal stuff. Though, that's a douche move.