>> My understanding is that if I did not have insurance, I would be responsible for paying the amount billed since I do not have the same agreement with the providers that the insurance company does. This is my biggest gripe about health insurance in this country.

Yes. And the drugs are that way too.
One of the reasons I took the Medicare drug plan is that the drugs cost a lot less to plan members than they do individuals.
Sometimes the difference can be in the hundreds of dollars for one prescription.
That seems outrageous to me. The uninsured individual has to buy the prescription and pay a penalty for not being insured on top of that.