If you leave it to that, most people don't care. They'll take whatever's cheapest, and what damage it does to the environment or other people is not a considera

If you leave it to that, most people don't care. They'll take whatever's cheapest, and what damage it does to the environment or other people is not a consideration. All of that stuff is happening far away, over long periods of time, but the nickel saved is right here and right now. If you want to leave it up to all 8 billion people in the world to take individual responsibility to end climate change, extinction, slavery, etc. then the approximate change accomplished is something approaching zero.