Politicians need money to get elected. Most politicians (with the exception of Jerry Brown) depend upon contributions from special interest groups to get elected. If they don't do what the special interest groups want, they don't get the money, then they don't get elected. The medical insurance industry is one of the most powerful special interest groups in the country. They certainly don't want anyone to tamper with the current system.

-- Along the same lines: I recently read a news article about state-produced prenatal information in North Carolina. The information contains no mention of the health risks to pregnant women of smoking. I guess you can't offend the tobacco industry.