volver you are eliding the necessary with the personal. No one said this ER founder shouldn't have a car, and use it, although many activists - and non-activists manage without and live places where they can, but this person was driving a diesel car.
The same with fruit and veg. Now I buy as much of my fruit and veg as possible in a market and I have reusable vegetable bags that I bought in Sainsburies (they still sell them. 50p each)
I also shop in the same supermrket as the one they were seen in, and rarely buy the wrapped vegetables. I buy loose fruit and vegetables, once again using my re-useable bags. I also try, wherever possible to buy UK vegetables. I just adjust my eating patterns and recipes, as far as possible, to fit seasonal patterns.
What we seem to be losing is the expectation that those who choose to lead and encourage us to reach high standards are expected to live up to the standards they set their followers.
If someone chooses to found and run an extremist global warming organisation, then I expect them to exemplify its principles in their life, what sort of example is it setting to demand that others do extraordinary things that make their lives difficult in order to combat climate change, when they are making very little effort themselves.