As a formerly obese American, I need to say you are both right.
The food ingredients in this country are, on average, garbage. With careful shopping you can get around this but it does take effort and vigilence.
Cultural expectations around both diet (especially portion size) and exercise (I cite the walking thing a lot too) are also bad. It takes effort to avoid those hazards.
I think both of these and probably a few other factors are a terrible combination that compliment each other in a bad way.
Portion sizes are a huge factor. My wife tried a few new recipes this week. All of them said they serve 4. We are a household of two adults and one almost adult and didn't eat half of what she prepared (they all tasted great).
That said, I'm 30 lbs heavier than I was a decade ago. I know WHAT I need to do (exercise more, drink less), it's just been hard to get back into better habits.
The food ingredients in this country are, on average, garbage. With careful shopping you can get around this but it does take effort and vigilence.
Cultural expectations around both diet (especially portion size) and exercise (I cite the walking thing a lot too) are also bad. It takes effort to avoid those hazards.
I think both of these and probably a few other factors are a terrible combination that compliment each other in a bad way.