Well, that turned in to quite the thread. I think that one of the reasons that threads about the food and health problems in our country blow up, here and elsewhere, is that the situation is pretty complicated and it's easy for people to stake out something they've observed about the problem and assume that all other observations are wrong. This is especially true when there's legitimate conflicts, where it seems if A is true, B can't be true. I thought I'd toss together some thoughts on how this has all gone down.
Arguments that explain away the lack of healthy home cooking as a matter of laziness and/or indifference to health when choosing food. This argument is appealing because it's not entirely wrong that a lot of people eat like crap because they're too lazy to cook at home, and they like eating junk food so much that they shove aside concerns about their own health. But this argument has no ability whatsoever to explain or predict what has been shown to be true over and over---that one's class background and income predict how likely one is to suffer the consequences of a poor diet and lack of exercise. If it's simply a matter of personal preference, or even a genetic tendency towards laziness or lack of concern for one's health/indifference to the subtler pleasures of healthier food, then we would see an even distribution across class lines of the phenomenon of thickening waistlines and correlating rates of diabetes, heart disease and certain cancers. Having a lot of money in the bank doesn't make a hamburger taste more or less greasy, but it can create an environment where you choose healthier options far more often.
Arguments that focus on the worst deprivations of poverty. I have a lot more sympathy for these arguments, because they're both true and they have predictive power regarding who will suffer the worst from a culture that downplays cooking and sells us on a bunch of junk food. But sometimes these arguments invite judgmentalism. Focusing strictly on those people who live in food deserts and have little to no access to ingredients or tools doesn't do much to explain the huge segment of people who do have pretty decent access to supermarkets and cooking tools and recipes, but still seem to suffer a diet and health penalty for not being in the upper middle class. Poor diet isn't just a phenomenon of poor people---as the study I linked showed, they were measuring folks who did in fact shop at grocery stores that had plenty of produce, but for some reason, they just weren't eating as well as the people shopping at Whole Foods. This is important, because even if we manage to fix the worst deprivations of poverty, and get the right things to people with no current access to fresh produce and basic tools, we're still going to have major gaps between the haves and the have nots.
The wide swaths of people who aren't poor but can't afford to be indifferent to the ridiculous prices at Whole Foods. The problem is that our policy approaches aimed at these groups of people tend mostly to be punitive in nature, which doesn't address underlying causes, can be wildly discriminatory even towards people who try to meet the minimum standards set by policy makers, and usually don't work anyway. Digging in to the complex but often understandable reasons that people avoid cooking even if they have seemingly adequate access is the first step towards crafting more effective solutions.