Diveheart accepts old wetsuits! They cut them up and people craft them into critters, pouches, bags, etc. that they sell to raise funds for the organization. I have a couple old suits I am going to cut up and use to make padding sleeves for my bike stand rather than clamping the frame directly when I can't use the seat post. My Gf has a carbon frame bike and while clamping the frame is highly discouraged, sometimes you have to if working on the seat post. If that's the case, I want padding on there.
They can also be used to make mats for cleaning regs, guns, fishing reels, etc.
I've also used an old thicker suit to make kneeling pads when working on my mower or washing the car wheels.
Just need a little imagination.
As for the old BC, that may be something that does end up in a land fill. Or as an educational aid or display item in a shop. I have an old horsecollar BC. I keep it around because it was given to me by a dear friend. Someday I may try to dive it. Just for the hell of it. I have friends who have some old double hose regs and I may borrow one and throw it on one of my old steel 72s.