I can eat for hours at an all you can eat buffet but I don’t want to become massive so I prevent myself from doing so, I’m now athletic build

So yeah willpower is a thing, I guess some people just want excuses

It’s a mix of willpower and habits, America has bad regulations on foods making that most foods have added sugars, portions in American culture are massive and everyone drives everywhere because cites were built for the cars.

In Europe we have strict regulations on food, with food scores on the packages telling you how bad it’s for your health, our portions are smaller and we generally prefer fresh ingredients to heavily processed products and most European cities are made for walking and cycling.

40% Americans are obese vs ~22% in Europe

You get the same with Australia another car centric country