Are we all doomed? Society is a cancer to the world.?

Does anyone else agree? Please stay with me. I just watched Avatar, the new movie by the same director that made Titanic. They made a very intelligent ogy in the movie. They compare the planet to a human brain, and that in order to survive they would have to live in harmony with their host planet. Us humans are killing off our planet slowly, like cancer cells would to a human brain. I don't see our money and power hungry society getting any better. What happens when the population reaches its maximum, all animal species die out, and every piece of land is inhabited by people. What happens then? What is the goal of human beings' existence? I mean, in the end, money is just a piece of paper, or a meaningless numerical value. The sad part is the most of us are aware that we are working against the harmony of this world, but nevertheless because of society, we are helpless to do anything to stop it, or merely even stop ourselves from doing our part in destroying our world. It's almost as if we have no choice, just like cancer cells. Just an interesting and depressing thought that I wanted to share.