Colonoscopies may catch cancer — but yield sketchy bills : Shots - Health News : NPR

Medical providers have broad leeway to determine how they bill for care, including by deciding how to identify what goods or services were provided. This means patients may get stuck with charges for unfamiliar or downright bizarre things. 

And because the law doesn't address how providers bill patients for preventive services, odd charges can crop up even for care that should be fully covered. 

Research also shows private equity ownership, which has been increasing in specialties like gastroenterology, can lead to higher costs for patients, as well as lower quality care...

https://www.npr.org/sections/health-shots/2024/01/25/1226552799/the-colonoscopies-were-free-but-the-surgical-trays-came-with-600-price-tags