True Scenario:
Go to Physician
He is employed by the hospital you work for.
Your insurance is through that hospital, your employer.
The physician has signed a contract with and is a preferred provider for your insurance- as your PCP.
You have a health condition that requires you to receive the pneumonia vaccination every 5 years.

You go to Dr.s office and they tell you the vaccine is not covered by your insurance. The cost will be $120.

You decide to go home and verify (5yrs ago it was covered same doc/same insurance)
The insurance company says it is covered.

You call the physicians office. You get the Tech. They say that “it is covered but they don’t pay me enough to do the shot. So we don’t use the insurance on that. You must pay the $120.”
Now another patient, with medicare, gets same shot- his insurance is filed. He pays nothing.