You're setting up an imaginary strawman. I grew up in the 80s in one of the most environmentalist households you could imagine. My mother was a local politician for the German Green Party, everything was ecological and fair trade in our household, from the food to everything else. She was fighting for windmills, against cars, etc. Our bread was baked by an ecological farmer with a long beard, for some time we fetched the milk directly from a local farmer, and so on. We participated in marches for peace and the protection of the environment, my mother helped voluntarily in the local fair trade shop ("3rd World Shop").
So I've had plenty of experiences with environmentalists over my life and heard many crazy stories, e.g. one of her friends really thought that honey is harmless for children but sugar essentially poison.
Despite all this, even the most radical and craziest person I've ever heard of does not fit the description of an environmentalist that you attribute to this subculture as a whole. There are radicals like VHEMT but these are in a ridiculously small minority. The vast majority of all environmentalist believe that it is perfectly possible for a large number of humans on earth to life in harmony together with nature while sustaining high standards of living. It's all about reasonable consumption and studying ecological lifetime calculations of products.
Where I grew up, Swabia in Germany, is a pretty good example of reasonable & realistic environmental politics. I used to make fun of many of her claims, proudly eating my bacon sandwich and visiting by plane, but it turns out in retrospective that she and her friends were right about most of the issues that most of the things my mother has been fighting for are now in the party programs of all major parties.