If we use the "it costs society" mantra, then unhealthy diets must be made illegal. Cars must be made illegal. Running, jumping, and playing sports of any kind will be illegal, although it is also illegal to not exercise. Carried to it's logical conclusion, everyone will be required to be encased in plastic and fed by tube. That way, society knows exactly what the cost will be from cradle to grave on a per diem basis. The only variables will be genetics, and those will be tightly controlled and monitored by the government with only the most healthy genetic specimens allowed to progress beyond initial conception.
Short of that, the "it costs" nazis are nothing more than a bunch of do-gooders who've discovered and emotionally-charged way to control someone else's life. The cost of society is, well... , the cost of society.
If you want to endanger yourself, fine. Just don't expect me to have much sympathy for your plight. But don't start poking your snotty nose into my business just because you don't approve of my lifestyle choices. And don't you DARE try to control my private lifestyle choices by whining about how it "encroaches" on your precious freedoms. If you think you are free to exercise your whiney control over me just because you don't like the way I live, I may feel free to burn your house to the ground. Hey, freedom isn't free. And you wanted to be in the fresh air anyway.
Brad