I think that they are terrified that they might have guessed wrong. I think they can't stand the thought that they might have made the wrong choice and that choice is going to eventually kill them, and the thought of us, the low-browed knuckle-dragging mouth-breathers being right, and surviving, just grinds on them. They would prefer that everybody all be wrong and all die together, than the "wrong" people be allowed to survive by making their own choices, different from theirs.