Is it possible the hospital also has a tendency to over charge? For example, the data for Synagis indicates it only works to prevent RSV in a very narrow set of cases. It's a very expensive medicine. And it's vastly over prescribed based on the efficacy data, so a parent who is already emotional over their premature baby is going to be frustrated if/when the insurance company denies it. The doctor isn't going to into detail and explain that the data doesn't support its use. They're incentivized to "do something", even if it's a shot in the dark.
For my wife's surgery (gall bladder removal - supposedly one of the most common in the country) insurance paid the surgeon, and initially denied the hospital bill and anesthesiologist bill as medically unnecessary. After 8 months of back and forth and dozens of multi-hour-long phone calls insurance finally covered it all.
I don't really care whose fault it is, I shouldn't have to play phone tag with two powerful entities over the course of 8 months as they try to figure out if they're going to fuck me over or not. It's a huge waste of time.
Yes, that’s why Kaiser is a nice model if we can’t get to taxpayer funded healthcare. It’s vertically integrated insurers and provider so there’s no in network and out of network and covered or not covered BS.