We eat a lot of crap in this culture . Any time you see a misspelling or invented word on a package of food, you're buying crap. Anything that needs to tout its health benefits on its packaging is probably crap. Anything that is fortified with niacin is probably crap.
But we're also eating a lot of decent food way out of proportion. Stuff that used to be reserved for special occasions has become daily fare, meat particularly. Ever made french fries? They're a royal pain in the ass! You have to wash or peel the potatoes, slice them into relatively slim fry shapes, wash the starch off them, pat them dry, deep-fry them once at 250 or 300 degrees to par-cook them, let them drain, deep fry them again at around 400, then let them cool while the delicious aroma wafts around your kitchen. They're hard work, even disregarding the issues with filling, maintaining, draining, and cleaning a deep fryer. If you had to do that kind of work for a fry, how often would you eat them?
Most cultures have two kinds of cuisine: the everyday cuisine, and the celebratory cuisine. The former is nearly always simple, vegetable-heavy, and often pretty tasty. The celebratory stuff (usually served at weddings, holidays, or other special occasions) tends to be heavy on meat, use lots of ingredients, take a long time, and taste really good. There needs to be a place in our diets for both of these kinds of foods, in the correct proportion. The problem is, we don't really celebrate with food anymore.  We don't as a culture really save much for special occasions -- the celebration cuisine has become our everyday cuisine. When we borrow food from other cultures, we tend to take the celebration stuff and leave the everyday stuff. 
Now, that's just what we eat. We have this ridiculous mentality that we ought to be "getting our money's worth" when we buy food, by which is always meant "get a lot of food". Listening to people talk about food, it's almost like they've totally lost the ability to gauge the value of a meal by anything other than the poundage and the price. It's nearly impossible to get an appropriate serving size at a restaurant without ordering off the seniors menu or getting an appetizer as an entree.
Many of us also were raised to "clean our plates" and not "waste" food. If we don't finish those ginormous portions, we're somehow bad people: wasteful as restaurant patrons, ungrateful as guests. I'd yell at my parents, but they got this from their parents, who got it from the Great Depression or something. I guess our weight problems can be blamed on Herbert Hoover. What a jerk.
So... It's screwed up that a journalist can make a handsome living selling books whose main thrust is "Eat food. Not too much. Mostly plants." But he makes that living because people don't know it, or at least haven't internalized it. Where would we get it from? Our parents didn't get it from their parents. Our government gets hammered by industry lobbyists and lawsuits whenever it tries to give it to us (when it bothers to try -- thanks ADM!). For every half hour of a helpful TV program like Good Eats or even The French Chef there are multiple hours of loud colorful ads for Chocolate Frosted Sugar Bombs and the latest incarnation of "corn chip sprinkled with flavored salt". And anyone who tries to take responsibility for changing it is derided as an elitist, a nanny-stater, or just a busybody. Not to mention the enormous pushback we're seeing in the Internet's near-worship of bacon.  Phew!
Now, I'm one of those people that I'm ranting about: at 30, I'm overweight (I lost twenty pounds over the last year, and am still overweight), I get precious little exercise (I manage to injure myself almost every time I try. Go me.), and as a result I already have a cholesterol problem. And I'm at an advantage, too: I'm an educated person here, lucky enough to have the free time to exercise and the spare (!) cash to buy quality ingredients; I know how to cook, I know how the human body works, I understand the basic concept that if you consume more calories than you use, you gain weight. But I like french fries, I like beer, and I do reject the notion that I should only consume those things if I make them. And I live in a part of the world that gets bitterly cold, making it unpleasant to spend time outside.
In other words, I have every reason to want to claim that this is a hard, nigh-unsolvable problem... but it's really not. It just sucks to consume less than I can: to eat less than I can, to drive less than I can, to take less vacation time or play fewer video games or buy fewer gadgets. Self-restraint sucks, and I resent it... but I have to admit that it's kinda important.
Socrates said that the unexamined life is not worth living, so maybe he'd say that it's a good thing than an unexamined life is likely to be short. And short it will be: The undisputed point is made over and over that what we eat, and how we eat, and how much we eat, is killing us. My dad always says, you gotta die of something. That's true, the current mortality rate is and will likely remain 100%. But it's really fucking embarrassing to be dying of this.
 I originally wrote "country" here, but Oliver makes the point that we share this with other English-speaking countries, and are exporting it around the world. I've heard it said that we got this eating culture from the British, but it doesn't really matter where it came from.
 The closest we probably come to celebration cuisine is the Super Bowl, when it seems sometimes that we have a hard time being noticeably worse than normal. Though, not too hard a time. (...wow, that looks tasty...)
Somewhat perversely, it seems sometimes that our holiday feasts are healthier than our everyday meals: we may eat a lot at Thanksgiving, but the ritual meal of turkey, sweet potatoes, green bean casserole, &c. is probably better for us than, say, your average Chinese takeout order. A lot of holiday parties I've been to for Christmas and New Years have had food that's more celebratory, but the "stand around, chat, and snack" model often results in eating less of it, as people eat more slowly and get a chance to feel full.
 The exception that comes to mind here is Indian food. The British have done a number on it, but it's pretty easy in most decent Indian restaurants to get a good healthy meal where the vegetarian options aren't pathetic. Sure, the cream-bases sauces and stuffed breads are prominent on the menu, but the good stuff isn't buried. For that matter, Japanese cuisine seems to have been imported more or less unmolested. Teriyaki's turned into a sugary mess, true, and ramen has been transformed from an often-sublime experience into a deep-fried salty disaster, but sushi, soba, and donburi have arrived mostly intact.
 ... which is, admittedly, pretty awesome. And really, I think the pushback is less against the notion of eating healthy than it is against the notion of ALWAYS eating healthy. Just as it's not healthy to eat mostly celebration food, I think it's just as unhealthy to never eat it. Too often a "healthy" meal is presented as a joyless one: an ultimately unsustainable tactic.