I stated that our poor baseline health is PART of the reasons our healthcare is so expensive. An upside down healthcare system that rewards sick care is very much at the heart of the matter. But compared to other first world countries, our obesity, diabetes and metabolic syndrome rates are at the top. We keep a lot of sicker people alive way longer than we used to and longer than we should.
You cannot argue against the obesity analogy and use smoking. The factors for nicotine addiction are also very complex and are on par with opioid addiction. Smoking was an easy target for the insurance industry and politically acceptable at the time. There are even politically incorrect analyses that show smokers may save on retirement and healthcare expenditures because they 1) pay high taxes on cigarettes and 2) die sooner and faster without necessarily dragging out healthcare expenditures like a lot of chronic conditions.
I am way more aware of the complex reasons for obesity than you are but most of our American obesity issues come down to poor lifestyle choices and a food industry all to willing to make a buck on cheap processed metabolically inflammatory food with our ignorance and willingness to eat it. And we have failed as a country in teaching healthy lifestyle choices in primary education. We have passed the tipping point where any politician and even most healthcare workers are not willing to flat out tell people that their lifestyle is killing them and straining the healthcare economy because we are almost more obese than not as adult Americans. But still, financially motivating people to reduce their risk factors maybe a major stimulus needed to reduce the economic burden of obesity.
Yes, there are people who have BMI's in the obesity range that are metabolically healthier than normal weight people but this is more the exception than the rule. When infected with Covid, obesity (even with normal metabolic parameters) in the non elderly population was overwhelmingly a risk factor for hospitalization and death. This was very much glossed over by both administrations, the CDC and the media. The vast majority of obese people could reduce most of their health problems with a 10-15% loss of excess weight. It sometimes isn't necessary to have a normal BMI.
So if you are going to single out the unvaccinated for insurance rate hikes then it is fair game to single out other relatively controllable health factors as well. Furthermore, you can now exclude rate hikes for natural immunity from Covid because it has been shown to reduce this risk of bad outcomes in subsequent Covid infections, especially true since Omicron's emergence. We should give credit for people who are seropositive for previous Covid infection as equal to vaccination if the data continues to show equal outcomes. I don't recommend natural immunity as a primary means of obtaining immunity however. People were really rolling the dice by waiting on natural infection.