It's lower than what the provider charges other insurers, that doesn't mean it's below the provider's cost. It's also commonplace for providers to bill insurers one amount but the insurer only pays a lesser amount, it's a little game they play. Pricing of medical goods and services in the U.S. are very divorced from the actual costs of providing them.

Also, Medicare and Medicaid can't negotiate drug prices.

I think so. My point is, government price ceilings on all health procedures are so noxious to half the polity that nobody will support it, and we'll get single payer by default.

They are generally less than what providers bill to others but Medicare doesn't pay below cost.

Medicaid varies because states have way more control and many states (especially Republican-leaning ones) have slashed their rates as part of a concerted effort to kill the program. Not that it matters - in Texas you generally can't qualify for Medicaid if you're childless or have a job. The income requirements are insanely low.

Sure, but that's why participation rate varies pretty wildly from one practice to the next on whether or not they accept Medicare or Medicaid.

If a doctor doesn't like the rates Medic[are|aid] are paying, they're free to not accept Medic[are|aid] patients.

Unless they are emergency room patients. :)

Fun fact: Medicare is prohibited from negotiating drug prices with suppliers, by law.

Ah, yes, Medicare Part D. That's what happened the last time the GOP got to write a health care bill.