Americans are allowed to chose whether they get certain tests or not; and whether they get treatment or not for stuff found by those tests.

America has a problem with over-testing, over-diagnosis, and over-treatment. It seems that merely giving people a choice, telling them the cost, and getting them to pay a contribution isn't enough to prevent this.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5708862/

https://jamanetwork.com/journals/jama/fullarticle/2662877