Many of the people who deny climate change and think that sustainability is just a bunch of tree-hugging hippie mumbo-jumbo are old geezers who are going to be in nursing homes or dead before too long. The next generation are the ones who are going to be in office, making the most purchases, and starting new companies.
The next generation is key. Rather than spending so much effort getting mad about climate change deniers (which accomplishes nothing whatsoever), why not work to start a local movement to change the local or regional public school curriculum to include sustainability education at the high school level?
One victory in this regard helps pave the way for more like it, and more like it yet.