That's quite a simplification of the situation. While shareholders technically "own" a company, they usually don't have that much influence over a companies policies.

This holds even more true with matters that will cost the company a lot of money while giving no added value to the shareholders, such as those externalized costs by polluting the environment.

Why would any Apple shareholder willingly take a hit to their portfolio just for a "nice feeling in the tummy about having done the right thing"? Not to mention that with most publicly traded companies there's only one "right thing": Increase shareholder value, everything is optimized around that and pretty much only that.

And sure you can vote people into Congress, but what leverage do you have that those people actually stick to their word once they are there? Imho that's one of the major flaws with most representative democracies: There's only positive voting, you can't "vote out" people who didn't hold up their end, you can only try to replace them with somebody who got more votes and hope he/she keeps their word.

In the end, this is also a question of how do we want our economies to be built: For supposedly perpetual gains and growth or for a sustainability which accounts for the actual scarcity of resources not easily measured and accounted for, like a clean environment.