Everyone benefits from you being fat. Your doctors, your car manufacturer, food manufacturers, everyone. Except maybe health insurance. But they're not hurt too too much.
The other 80% must be paid to healthcare providers.
This means that if health insurance companies want to make more profit, they have to increase premiums so their 20% cut grows and they can only do that by increasing healthcare spending.
Well, there are other ways. For example, Aetna owns CVS, UnitedHealth owns OptumRx, Humana owns Humana Pharmacy, and so on. They get to pay themselves to provide healthcare. This provides a big incentive for insurance companies to want drug prices to increase. They can raise premiums and collect profit on filling those expensive prescriptions.
There's plenty of doctors and surgeons who wish there were less fat people, because they enormously complicate doing surgery on and managing in hospitals.
I agree, but this isn't how incentives work.
Ultimately, there are billions of dollars at play here that rely directly on obesity. The mechanisms of the market and human behavior transcend moral judgement.
What about everybody that works in liposuction?
They want to "fix you," too.
The car industry is a huge one. Making people drive everywhere means more car sales, more fuel sales, more infrastructure built for more cars. And it also makes you fat as a side effect.