I understand your concerns and that bleak scenario is indeed a possibility. I am much more optimistic about the ability of mankind to overcome its challenges and shortcomings. I am a firm believer that we can innovate our way out of any problem, so long as the will is there.
But I also like to explore dystopia. My take on the real danger to human civilization is here: https://medium.com/short-bytes/artificial-intelligence-will-be-the-end-of-humanity-but-not-for-the-reasons-you-think-482fbfa6858f#.cynrtjtn1