I absolutely care about human life, and it's sad and senseless when people kill themselves with stupid choices.

I just respect their humanity enough to not impose my will on theirs, when their decisions don't cause significant enough externalities for the people around them to justify treating them as less human than I see myself.

Seatbelts decrease auto insurance costs.

And legal penalties for high BMI decreases health insurance costs, which are much, much higher than car insurance costs (as well as preventing far more needless deaths, since you're such a humanitarian).

Why is freedom of choice valid in the more egregious cost scenario but not less egregious one?