I agree to a point that it's the food Mummabear, but as a bottle fed and spoon fed child of the 70's, my siblings and I were active kids who were skinny because we weren't over-fed (there wasn't the money for constant streams of food, and we were expected to eat what was on our plate).
Once we were a bit more affluent and made those decisions for ourselves we are all overweight and my siblings and I don't know when to stop-we eat what is there and keep going to an empty plate, which I think is mainly due to the attitude of not wasting back in the 70's & 80's, but starts with babies being gently coerced into having more and more.
My mom says it was all about filling us up-rusk added to bottles, extra spuds etc. it's understandable as that's what the advice was, and if money was tight you wanted kids to eat everything given so they weren't hungry later on.
I definitely think it's contributed to my unhealthy relationship to food-at 41 I'm trying to learn how to not overeat and leave food on my plate, rather than power through and end up feeling stuffed!