Convenience is another factor. Unless you live adjacent to a grocery store, you are almost always nearer to a source of junk food in the form of a convenience s

Convenience is another factor. Unless you live adjacent to a grocery store, you are almost always nearer to a source of junk food in the form of a convenience store or fast food restaurant. Neither are likely to be cheaper than what one can make easily from generally healthful ingredients. (Cheap comes into play e.g. with chain sit-down restaurants, who get around the problem of having mediocre food by serving it in comically huge portions slathered in some unhealthy flavorizing agent like butter or Ranch dressing. They can probably beat anything you can make at home in terms of price per calorie. The meal doesn't actually get cheaper, meanwhile the impact on your health is worse because you're buying a whole lot of calories you don't need.) In poor communities I've seen it's sometimes the case that shopping at an actual grocery store can be a two or three hour round trip due to bus schedules while the corner store is a five minute walk. Both also profit immensely from the wealthier car culture: fast food could not be what it is today without the drive-through window and people's eagerness to consume meals in their cars, and the typical convenience store is a convenient source of food because it also happens to sell gas, which every driver needs. Both allow the consumer to trade away money and health for immediate satiation.