I think you make a good point. In the case of my wife’s surgery, I have to acknowledge that since I knew that the costs would significantly exceed our $3000 deductible I did not pay particular attention to the hospital bill. We did, however, blow the whistle on the PT who charged for a visit that did not happen.
However I do not think removing third parties is entirely the answer. Pricing of medical services is essentially monopolistic at the point of need for all but discretionary treatments - therefore, I think belonging to a group that negotiates prices ahead of time makes sense. In addition, insurance for major medical expenses also makes sense just as car insurance makes sense.
I agree, a major medical plan is worthwhile. But a relative recently had minor surgery and saw her two day hospital stay come in at $2,500.
It would be tough to negotiate this service since there are far fewer hospitals than car dealers (an example.) Competition is the solution, somehow.