IMHO. I try to dive with the philosophy of leave the ocean as I found it or better. On more than one ocasion have I been on a recreational dive when my buddies and I have come across debris. Most often it has been abandoned traps, line or ropes that do not belong on a reef. I carry a large collection bag and a knife and will bring the rope back with me. When we cannot bring all if back we cut as much as possible and remove it. Also, it is better to have it and not need it than need it and not have it.