Parents are to blame, though, which parents is up for debate.
If your parents give you too much food and teach you simply put, bad eating habits, portions that are too big, too many carbs, not enough healthy protein or good fats, then you've been taught to eat badly and this is where maybe a lot of fat people get a bad rap.
Eating becomes a habit, and habits are hard to break especially one as fundamental as eating. You physically change your taste buds, someone who eats lettuce from their first solids and nothing else, will love lettuce and not really "like" anything else, it will all be weird and wrong to them for life. If someone gave you sweet things as a kid, you'll simply have a sweet tooth all your life and find eating healthily FAR more difficult than someone who was taught to eat healthily as a kid.
Either way, which parents are too blame is a good question, if you were taught to eat badly, and can't break that habit and eat in such a way either infront of your kids or have your kids eat that way. Is it entirely there fault, or the people who taught them to eat that way.
I think its a bit of both probably, its even more difficult if someone eats badly as a kid, continues to eat badly but never has any health or weight problems so they have no idea that eating the same way, or same amounts for other people including their kids could lead to weight problems.
Ultimately parents are responsible, they need to teach their kids good eating habits, things like hiding chocolate and puddings is shockingly awful and something my parents did.
Kids who have crisps out in the open to eat when they want then generally speaking want them less and they are much less likely to binge on them. When you hide something you give it power, a kid wants something that is hidden more than something they can have any time, and when they find it they'll eat everything they can find because they might not find it again.
So many parents I knew as a kid and now as an adult do this, its insane. If anything leave some chocolate out and hide the fruit
But parents who have say one kid who plays football 10 hours a day, and another kid who sits in his room reading, then at dinner they give them equal portions and do the old "you can't have pudding/leave the table till everything on your plate is gone"..... again horrifically bad parenting. Let your kids eat till they are hungry, and no more, never ever once in their entire life force them to eat more than they want, ever. Stomachs expand, massively, again its learned behaviour, its a mental thing you can't beat, if you eat huge portions your stomach expands more, it becomes easier to expand and it takes more to feel full. Given large portions as a kid you'll always want a large portion as an adult, you stomach will expand more expecting more food and your brain will always feel less full than someone used to smaller portions.
So, give kids small portions, more frequently if required, if they start to gain a bit of weight, cut back a bit of food, TEACH YOUR KIDS that a bit of thinking and smart eating now will save them a lifetime of problems. Don't hide food, its god damned unbelievably stupid parenting, and never make ultimatums about finishing everything infront of them. Don't treat all your kids the same, dont' assume they'll eat as much as you, etc, etc.
It isn't helpful though that even if you give your kids great food, in the right quantity, a friends parents could feed them complete rubbish or way too much food, and food at school is generally ruddy awful as well. Why we feed kids at school pretty horrendously bad food, both poor quality, not well cooked, when fuel for learning is freaking ridiculously important I don't know.
I'm going to hell....
You do know how that works - populations and individuals ... how we measure stuff across populations and then know that not every individual in that population will demonstrate what we found for the body of people.
