> It is the only good/service in America in which the prices are known/paid only AFTER the services are rendered.

this is not really true. if you are having nontrivial repairs done on your house or car, they will give you an estimate upfront, but there can easily be unforseen problems that cause the work to cost a lot more. you might decide to have your car fixed later, but it's hard to pull the plug on a kitchen remodel halfway through. there's all kind of work that gets done without knowing how much it will cost beforehand.

You're right, I was being hyperbolic.

I'd qualify my statement with preventive* healthcare, the near entirety of which can function on upfront prices.

to your credit, I can't think of another field where there is so much uncertainty over how much something will cost when they already know exactly what they are going to do, what materials they will need to do it, and how long it will take.