Medicare patients are a net loss for hospitals and doctors. Hospitals and doctors never want to turn away patients, but if it is the only move left, in order to stay in business, you gotta do it.
According to folks I know who work in the medical billing industry, Medicare and Medicaid (with Medicaid being the worst) pay 25 cents on the dollar. My family doctor has a quota that he accepts each year and when he's over that he cuts it off. I can't say I blame him. He has overhead and salaries to pay, obviously with his being the most important. The unfortunate part about this trend is when the government gets enough people on tax payer dimes doctors won't be able to say no to patients because there won't be enough quality patients left. When that happens doctors will leave the field and flock to more profitable professions, like trading
Hospital bills are the source of the problem. Doctors bills (in my opinion) are frequently in line with what I would expect to be paying they for their time. Especially when I am paying cash because of my big deductibles.