Just because you can dump industrial waste into a river doesn't mean you should. Just because you can steal doesn't mean you should. Just because you can shortchange citizens doesn't mean you should.
Yes laws should be passed, I agree, but that doesn't mean we can't also multilaterally also go after others at the same time. Do you hold the parent responsible for the kid stealing? Yes. But you also hold the kid responsible for stealing.
Most of all, I want to get of this notion that public corporations have fiduciary responsibility to maximize profit. In the Supreme Court case Burwell v. Hobby Lobby, the supreme court stated that "modern corporate law does not require for-profit corporations to pursue profit at the expense of everything else, and many do not do so. For-profit corporations, with ownership approval, support a wide variety of charitable causes."
There is a better option, we just aren't taking it. As citizens, we should be supporting multilateral action for a more ethical capitalist economy.