Adults are adults, though and are responsible without nannying to make sane choices. A big enough deal has been made about calories, fat, and nutrition that there is no excuse not to know to seek not to live on hamburgers and milkshakes alone. Even yet, beside the meager fare of more sickly ancestral times, a hamburger diet would be a comparative godsend.
I’m sure it’s possible to make less-fat, less-sugar versions of most fast food items. Baked rather than fried, and that kind of thing. Nobody’s clamoring for them or they would be offered.
You’re right, it’s market driven. And, I’m not above being a long term investor in a very large fast food operation. “I’m lovin’ it.”
We do the best we can, we do. ;-)