You might get an operation in a hospital and stay one night. They could tell you the cost of the bed, but what about the lab tests (which is another business unit). Then you've got nurses who might work across two different units. Then imaging which is another unit.

My friend who worked at a major hospital said it's a massive shit show. For simple out-patient procedures, they have the costs down pretty clean. But for in-patient stays, they often have no clue at all what the real costs are.