Yeah, the landfill space thing is a great point. I tried using some reclaimed Romex once and learned the hard way. Pulled it out of an old attic and the heat up there had made the insulation super brittle. Soon as I bent it into a new box, the jacket cracked. That's just asking for a short. Saving stuff is cool, but not when it could mess with the whole system's safety. The risk isn't worth it.