I wrote an extensive piece about it.

https://democraticunderground.com/100219801308

When those two government programs started, providers were paid based upon what they charged in the one or two year period prior to the medical service.

Docs/Hospitals learned quickly to increase charges, even double or triple what the charged the year before. The government learned quickly that providers cheat and developed reimbursement rates based upon a flat fee to stop the cheating. The reimbursement scheme used by Medicare and private insurers meant that charges are basically irrelevant, unless one is uninsured or the service is not covered.

In almost all insurance plans and Medicare/caid, a hospital might bill $100,000, but the insurer says the approved flat rate is $15,000. In that case, the provider has to write-off the difference between $100 K and $15 K (and no they don't get a tax write-off as some people think).

Doctors and hospitals also know that uninsured patients are not likely to be able to pay the inflated fee. Therefore, they are quick to to reduce their fictitous charges when an uninsured patient asks.

I usually tell uninsured -- or even in cases where Medicare or private insurers offer no coverage (say brow surgery that is more cosmetic than functional for eyelids interfering with sight -- to offer the provider(s) a bit more than Medicare's rate and see what providers say. They will amost all accept a lower payment, but not necessarily Medicare's rate.