The assumption has always been that the drive-through is a place where people go to feed their families on a budget, but that's not the case

For years the conventional wisdom has been that fast food is poor people's food; that, thanks to government subsidies that ensure cheap calories, the drive-through is where people who can't afford the "good" stuff -- organic, grass-fed, etc. -- go to feed their families on a budget. Why else would anyone eat that stuff?

But a new study to be published in the Journal for Population Health Management reveals the dirty little secret of the American middle class: It's not cash-strapped Americans who are devouring the most Big Macs and Whoppers, it's us! According to the study, a household earning $60,000 a year eats the most fast food, and one bringing in $80,000 is actually more likely to have it their way than one with $30,000. Suddenly, last year's news from the Centers for Disease Control makes sense: Nearly half of obese adults in this country are not poor but middle-class, earning at least $77,000 for a family of four.

The unpalatable truth is that fast food's attraction has never really been just about price. For all you hear about the Dollar Menu, a buck at McDonald's buys a small burger, or small fries, or a small drink -- hardly a satisfying meal for most people. As Mark Bittman reported recently in the New York Times, a typical meal for a family of four at McDonald's in Manhattan costs about $28 -- far more than what it would cost to make a healthier meal at home. For someone who's really pinching pennies, a trip to McDonald's makes no sense.