That is the dark side of environmentalism, an ugly violent side that emerges easily. The most active non-Muslim domestic terrorist group is environmental. The undercurrent of violence finds easy purchase in environmentalism's creed that the only real problem with the world is the people. No amount of turning off the lights is enough. Eventually you come around to having to turn off the people.That's really what it boils down to: an ugly undercurrent of nihilism. There's a sense of, not so much a love for nature, but rather a loathing for humanity.
On a related note, how come I never read about these voluntary human extinction types suck-starting a Mossberg? How come it's always everybody else they want to go extinct?
(H/T to Kevin.)