Especially when one takes into consideration these facts: the costs of cleaning up after the natural disastors they help cause, if they can even be cleaned up quickly and succesfully, (see the katrina clean up, then imagine one or two of those every year) can be prevented by in part not using them. The fact that new green clean power gets cheaper every day and coal, oil and other non-renewable energy sources get more scarce every day and are many times located in hostile areas. The fact that there would be great loss of life and habitable area and expense involved in nuclear power accidents or terror attacks. The fact that damage to the environment and the current mass extinction of species is caused by them from the climate change they help cause. And the most critical fact, the disruptions to the global food supply that will result from there continued use. http://en.wikipedia.org/wiki/Obsolescence
The abondonment of old dirty power would lead to an explosion of the green energy sector and that sector would be able to meet demand as it increases in size to fill it.
Why do something vastly more expensive and destructive then something else that will serve the same function in a much improved way?