Generally speaking, if I have somewhere to put it or can easily carry it, I'll pick it up unless it's already got growth on it. Strangest piece of trash I've carried during a dive: On a day off during my IDC, I was tagging along with the DMT at the back of a group when the guide picked up what looked like a 6ft fishing hook (minus the barbed tip) and handed it off to the DMT... somehow I eventually ended up with it for awhile.