Why worry about the future if they say the world will end soon?

Fundamentalist Christians tend to find the notion that puny humans could influence the weather in some significant way to be a blasphemous denial that god is in control and has given over dominion of his creation to his people. If this led to a sense of responsibility and stewardship for the environment and the creatures living within it, that would be one thing. But for fundamentalists it is just cover for a sense of entitlement to pillage the environment at will. Because as you point out, god will either protect or provide for his own, or rescue them, from any consequences.