It's weird that you can't see the prices for those things and that the insurance companies pay a different price than individuals. That's evidence there isn't

It's weird that you can't see the prices for those things and that the insurance companies pay a different price than individuals. That's evidence there isn't a functioning market for most medical services in the US. But it's not weird that the insurance company wants you to get a flu shot or exam, since those things prevent them from paying out more money later. In reality there is some cross over point, where the flu shot isn't worth it for younger people, and is for older people. If you are young/healthy, get the flu and totally recover with a few Tylenol, and no insurance claims, then it clearly wasn't worth a $10 vaccine to prevent. That's the analysis for the insurance company. Depending on how you value your time, and time spent sick, your individual analysis may be different.