This August, taking a trip to the produce section of any Wal-Mart in the U.S. will yield a cornucopia of fruits and vegetables similar to that of any other Wal-Mart in the country during any other month.

Whether it be fall or spring, June or January, many of the same items will still be in stock.

So, how is it possible that somebody in, for example, Bismarck, North Dakota could sit down and enjoy a watermelon on Christmas, despite the fact that the city experiences an average high of 26 degrees for December? Simply: that melon got north by way of fossil fuels.

To some, the perceived environmental costs of such methods of food distribution are startling, and have given rise to today’s local food movement—the proponents of which (known as locavores) claim that more responsible alternatives can be found in buying food “locally” (unlike USDA organic certification, there’s no agreed upon definition for what constitutes locally grown food). And, while the environmental reasons for buying locally are noble enough, the reality of this aspect of local foods is something quite different.

According to author Brian Dunning, the produce of a traditional grocery store may actually be more environment-friendly than the fruits and vegetables of a farmer’s market due mostly to the grocery store’s use of a distribution center for foods. Distribution centers serve as hubs between farmers and a retailer, where a single truck may travel from a distribution center to many different farmers then back in order for the food to be delivered to supermarkets in the region.

Dunning writes that since most local food sources lack such a hub, tracing the paths of trucks from the retail point to the farms becomes a massively cluttered “starfish”, while doing the same for a system using a distribution center leads to a set of much more efficient paths. By not having to run wasteful, overlapping routes, grocers are able to save money that would normally have to be spent on diesel for trucks.

This bottom line issue of increasing profit is what ultimately contributes most to the improved efficiency and smaller carbon footprint of traditional grocers.

Others in the local food movement argue that when a food is available regionally, importing it from thousands of miles away is environmentally irresponsible, but that unscrupulous grocers do so anyway because it bolsters revenue. They seem to ignore the reason for improved revenue, however, which is, again, lower costs due to fewer resources being utilized.

The truth is that certain foods, particularly animal goods, will naturally be produced more readily in specific climates and, therefore, require fewer resources, resulting in less money to produce a yield equal to that of a less appropriate climate.

Then, there’s the final alternative from locavores: if something’s not in season in your area or never available, for that matter, then you could always choose to just not eat it. Sure, North Dakotans could probably go without a Christmas melon, but diversity is essential to a healthy diet, and limiting oneself to what could possibly be only a handful of foods grown regionally would be nutritionally detrimental, not to mention downright unexciting.