When I was a kid, we always had schmaltz in the house. My grandmother would use it to cook, because under kashrut Jewish people couldn't fry foods (esp. meat) in butter or lard. Now, my grandmother was not particularly religious -- the USSR had a tendency to beat the Jew out of you, and religious assembly was banned anyway. So why did my grandmother bother rendering shmaltz and storing it in the fridge when she could have just as easily used butter bought from the store? Because it was just something her people did!
Climate change these days is the same way. There are some people who continue to insist that climate change is a hoax. Maybe the Chinese are to blame, or maybe it's the scientists who are living pretty off the government dime while doing research in some of the worst conditions on earth. But the real reason they insist that climate change is fake is because that's what their people do, and the people who believe that climate change is real are the other people.
The fact is that evidence for climate change is incontrovertible. We've known the mechanism