I do wonder if we're now in a situation where the overweight parents of overweight kids, were themselves mostly brought up in household where healthy eating habits and an active lifestyle were not common? All the posters and TV adverts in the world are not going to help if people have had it ingrained in them from day one that they can eat whatever crap they want, not get any exercise, and that if they then put on weight it must be because it runs in the family/it's genetic/they're big boned/they aren't actually that fat etc etc
I don't think we've all become greedier or generally more inclined to get fat, but I do think that (especially people of my generation, I'm 28) we've become lazier than our parents. And eating healthily, esp on a budget, requires planning and effort. Feeding your child healthy foods is more difficult than letting them eat crap. And that, to me, is the crux of the problem. Plus cooking takes time, and no one seems to have enough of that.
By no means am I the best example, but now we have DS, we try really hard to have healthy food and activities just be a normal part of life. It's not as easy as some would like to make out - if you are not naturally a sporty, active person, it can be a bit of a drudge to try and keep active. If you have a mega sweet tooth, yo uhave to learn to restrain yourself and not indulge it too often etc. All this has to be learnt, and trying to reteach adults a whole new way of looking at and thinking about food and lifestyles, is not as easy as saying 'well, she should have just read the label'.
Do I judge fat parents with fat kids? A little bit, but I try not to because you don't know their circumstance, as a PP said, they might be on Day 2 of a mega diet and lifestyle change.
If someone is offered help time and time again to change their lifestyle and give their kids a healthier start in life, but they ignore it or can't be arse, and the child's health is at risk, then I would class that as neglect, but I wonder how common that really is?