to get back to the original question, I just wanted to point out that in single payer systems they introduce competition in different ways. Instead of how much a dr can make by endorsing a certain drug, he gets paid more from the gvt by lowering your blood pressure, getting you to quit smoking, having reg check ups..

So there is competition in single payer systems between dr's and medical companies, but the flow of wealth is not one designed to increase a share holder's wealth, but instead to the dr that does the best job.