The problem of billing is multi-factorial.
1 - The hospital has to spread out the cost of the device, upkeep, and personnel over all patients that use the device.
2 - The hospital negotiates a payment with insurance companies. This has to be lower or the same as for uninsured patients. If the hospital low-balls what they charge uninsured patients, all insurance companies will get the lower rate.
3 - The hospital negotiates with the insurance companies every year or so. If they don't come up with an agreement, the hospital becomes "out of network" and a higher percentage of the bill goes to the patient.
This leads to hospitals charging 3-5x for uninsured patients what they charge to insurance companies. As a patient, you can call up the hospital billing and see if the charge can be lowered or waived. They are surprisingly negotiable at times.