While the snack industry grew a mere three percent last year, the 100-calorie pack industry within it swelled nearly ten times as much, with annual sales reaching $20 million.

But the snack-pack attack cannot be attributed to value. Sweet or salty, the small servings are sourly priced. On a per-ounce basis, the Oreo 100-calorie packs sell for almost three times as much as regularly packaged Oreos. And while 100-calorie packs of Sunshine Cheez-Its go for $11 per pound, a pound in traditional packaging is a relative steal at only $4. Compared to a 6.5-ounce tube of Pringles, the 100-calorie pack has more than a 200 percent premium on a per–pound basis. A pound of lead and a pound of gold understandably sell for different prices. But how does mini-packaging magically transform lead into gold?

The higher price of snack packs cannot be attributed merely to higher packaging costs. Although individual packaging certainly boosts manufacturing costs — and imposes additional costs on the environment — consumers pay more than enough to swallow the differences. On single-serving packs, snack companies are left reaping 20 percent higher profits.

So there must be something else in those little packs that gives consumers big utility.

The higher price of snack packs cannot be attributed merely to higher packaging costs.

Is it convenience? As one report put it, people “pay extra for products they perceive as making their lives easier.” It’s true that we buy salmon or beef steaks instead of whole animals and “baby carrots” or broccoli florets instead of whole vegetables. After all, our time is valuable.

But American bloggers consistently report that it’s not just laziness keeping them from doing the portion control themselves. As one blogger admits, if forced to bag single portions, “I'd probably be tempted to snack while I bag.” Why would he be tempted to snack if he’s clearly portioning for weight loss?

Enter the theory of time inconsistency. Time inconsistency assumes that an individual has different preferences at different stages of life. My future self, for example, wants me to eat at most two Oreos this afternoon because she doesn’t want to suffer from obesity, hypertension, or low self-image. Yet my present self craves the sweet sensation and subsequent sugar-high of mindless noshing.

This wouldn’t be a problem if we could perfectly balance the interests of our present and future selves. Yet economists have found that individuals tend to put a disproportionate amount of weight on their present utility – and thus on their hinnies. This leaves us occasionally binging on Oreos; and, on the aggregate, it leaves us worse off.

The time inconsistency model can be applied not only to weight control, but also to procrastination and to addictions, such as smoking. Although a smoker’s future self does not want lung cancer, his present self craves the nicotine high. Eighty percent of American smokers want to quit. Yet because most individuals tend to overvalue their current desires, many who want to quit don’t. And this comes at a high cost to the smokers themselves.

Herein lies the rational for an excise tax. Even putting aside the negative externalities of second-hand smoke, cigarette taxes can benefit society by helping smokers find the will to quit: the higher prices of taxed cigarettes may provide additional incentive to overcome their addiction. Surprisingly, then, excise taxes on cigarettes may actually make smokers better off. Data from long-run surveys in the U.S. and Canada say that smokers have a self-reported greater well-being when cigarette taxes are raised. And state representatives are listening. As of August 1, Delaware raised its tax rate on cigarettes to $1.15 per pack, putting it just above the overall states’ average of $1.07.

Similarly, countless American bloggers report being better-off despite having to pay more for snack packs. On The Consumerist one blogger writes, “Buying the 100 calorie packs has helped me curb my overeating habits tremendously.” How so? Another blogger explains, “The experience of ripping open another package really hammers home that you're eating more and more.”

A two-hundred percent premium seems like a hefty price to pay for slimness. But what’s the relevant comparison? Perhaps the diet and weight control supplements on which Americans spend over $1.3 billion each year; or the over $2.4 billion spent annually in America treating obesity; or the $9 billion annual indirect costs of obesity (including lost work productivity and unemployment). Paying higher snack prices for smaller servings may be a form not only of self-control, but also of preventive medicine. If we splurge on the snack packs today, our future selves may thank us.

Seven years ago, DC joined the rest of the United States in eliminating its snack tax. But does the time inconsistency model imply that the states should return to taxing snack food just as they tax cigarettes?

Not necessarily. It’s not clear that it’s the higher prices – as opposed to the smaller portions – that are making snack packers practice moderation. Therefore, without the portion control, there’s no reason to assume that snackers’ consumption would fall with rising price. To the contrary, the ballooning sales of snack-packs – and waistlines – amid ballooning prices indicate that the demand for snacks isn’t very sensitive to price after all.

And snack taxes have their downsides, mainly that they’re terribly regressive. In 2004, households with annual incomes below $10,000 spent 12 percent on snack food, while those with annual incomes above $70,000 spent only 1 percent. That means that a snack tax would hit the poorest hardest. So until we figure out the extent to which higher snack food prices could discourage overeating and prevent obesity, we’d be wise to continue to keep state snack taxes at bay.

In the meantime, though, feel free to tax yourself. Spend big on those little packs. It just may slim you – in addition to your pocketbook. After all, as any Pringles eater well knows, “Once you pop you can’t stop” – at least not until you reach the bottom.

Emily Glassberg Sands is a research intern in health policy at the American Enterprise Institute.

Image credit: 'Snack bowls' by Flickr user Unhindered by Talent.