Steve I think we are probably all more in agreement that not. The trouble with one paragraph responses is that they make points, but in isolation.
I think we can agree that more could be done to educate people about nutrition and this is across all socio-economic groups.
There is a subset of people that are functionally illiterate.
We closed asylums to advocate care in the community,yet some are reduced to having a cardboard box in a doorway as their home. We all have heard of lottery winners that have squandered everything after a couple of years. There are low skilled jobs but no unskilled jobs. To be employable you have to be able to follow simple instructions and obey legitimate orders. For a small minority that is a step too far. So there will always be people outside the continuous care system but unable to do an adequate job of looking after themselves. A basic analysis of the homeless figures give a truly frightening picture. " More than half of young homeless people were excluded from school growing up, 40 per cent experienced abuse at home, 33 per cent self-harm and 30 per cent spent part of their childhood in care. Theoretically they should be targeted as a priority group. In practise, NOT SO. A quick search will find many articles to back this up. Until more is done for disadvantaged children this vicious circle will not be broken and the cycle will continue.

Some prepackaged meals are cheaper than trying to accomplish the same with fresh ingredients so it is hardly surprising many choose the microwave option. It is both fast and effortless.
   Besides the above facts the modern world has virtually eradicated hard graft, yet many eat vast amounts of calories without giving a thought to burning them off, hence rising levels of obesity.

I see no point in fingering the bottom of the heap. Far more would be achieved by fully understanding the various factors that spawned their misfortune. I am sure any reasonable teacher can see those children that society is failing, but short of outright abuse, what does society do about it? I have only outlined a couple of snapshots, obviously it could be vastly expanded.