Why tie them at all?Well, once everyone is across the bridge, it can be dismantled and the rope retrieved. But yeah, six distinct uses of rope is going to tap us out, and it's likely we'll need it later on. Assuming each of us has the standard 50' of rope, we could tie the corpses up now as we search the room, but take them back before we leave. But I wouldn't want to leave our rope here.