When I see thinking like this, it makes me truly sad. I am torn between thinking you are a rational actor and a self centered dipshit. I think about the tragedy of the commons (http://en.wikipedia.org/wiki/Tragedy_of_the_commons). The rational thing to do is to grab everything you can-- the inevitable end is total devastation.
If you grow bacteria on a petri dish, they will grow until nutrients are depleted and waste products accumulate-- then they die. A few centuries ago, the earth was in a self sustaining state. Population growth was kept in check by our ability to get enough food and calories. Starting with the industrial revolution we are now able harness the energy stored over millions of years (petroleum hydrocarbons) to push mountains, harvest the desert, build skyscrapers, send robots to Mars-- truly awe inspiring achievements. Now population growth is not food/calorie limited-- I can take $3, head down to the corner 7/11 and get more calories than are good for me.
I worry that humans have "evolved" such that they are now able to replay the tragedy of the commons on a global scale. I think that if we as a global community can't come together to solve these issues then we deserve what we get. What makes me very pessimistic about the future is that deep down inside, I think you are both a rational actor and a total dipshit.