Why should I when local, state and federal governments won't?

It is called character. You do what is "right" because it is the ethical to do. Doing the ethical thing does not depend on whether everyone else is also doing it. That is why we have pioneers, martyrs, and others who did what was "right" in the face of societal opposition or apathy. If you care about the environment and believe that it is threatened, then you do what you can to soften your impact, regardless of whether the rest of the world notices or cares.