I guess I don't agree with the authors premise that "it’s not so much the greenness that matters as being seen to be green." In fact, it is the greenness that

I guess I don't agree with the authors premise that "it’s not so much the greenness that matters as being seen to be green." In fact, it is the greenness that matters, and the author is just self-conscious and wants to appear green. Who cares what other people are doing? If you can pick up a biodiesel fuel car for a "song" and use free/cheap vegetable oil, why not just do it? You are saving all the emissions related with producing a car and transporting it. I know in many cities they have EU 3/4/5/6 requirements to drive inside the city, but I would hope that a car that runs on vegetable oil satisfies these requirements.