That also doesn't work because that same precedent can be used for other preventative health issues such as obesity. "Well, you shouldn't have been eating all those cheeseburgers, sorry"
I think you have a point, it's a fine line, but say there was a shot which could prevent you from becoming obese and all the problems that come with it? Now I'm going to kind of argue against myself here, but as I write this I think a better comparison would be Flu, you can get a Flu shot and pretty much stay out of the hospital. People end up in the hospital with Flu every year and insurance covers that. I guess this is all to say after some reflection, I can see both sides to the argument.