My wife does a lot of PR and marketing for healthcare and pharma. She often comes across ethical problems that just cannot be solved in an entirely free market.
Take for example cancer. Big money for a lot of health care systems, hospitals, doctors, and pharma companies. There's genomic research now that shows that women who run negative for a certain genetics test on breast cancer have only a 1 in 9 chance that chemotherapy will do anything for them at all -- i.e., besides costing a lot of money, making them puke their guts out for several months, and making them lose all their hair. But the oncologists themselves run chemo labs, etc., so all their profit motives are set up to push all women with breast cancer through the chemo machinery regardless.
Only an outside agency, such as government oversight, is in a position to prevent a lot of people making tons of money to do nothing but make a lot of people unnecessarily much sicker and poorer under the fake auspices of "doing everything necessary to treat their breast cancer".