Kind of overstates the case, TinCook.
The locovore movement would be more a return to the last half of the 19th and first half of the 20th century; a time when, as Foodpump pointed out, cities were ringed with truck farms who delivered fresh, ripe produce on a daily basis.
This is, essentially, the sort of thing done at legitimate farmers markets.
The primary differences between that and the modern factory-farm system is that, thanks to both varieties grown and methods of growing, the produce was flavorful and nutritious with the old system. The same cannot, necessarily, be said for the modern one.
When varieties and growing methods are choosen to meet the needs of the food distribution system, flavor and nutrition, when present, ride in on the shirttails of the genetic choices. The selection criterium include: pest and disease resistance; ability to withstand the abuses of truck, rail, air, and ocean transport; uniformity of size, shape, color and ripening times; ability to withstand long-term cold storage; and similar characteristics.
The food distribution system also defines things in ways that go counter to consumers' intuitive reactions. For example, under the law, a vine ripened tomato doesn't mean it's ripe. It means it has passed the breaker stage, and, in some juridictions, shows "some" color. That's a long way from being ripe.
The primary benefit of the modern food distribution system is that it provides large quantities of food relatively inexpensively. As a co-committment, it allows off-season foods to be delivered anywhere in the world. This is not the Devil's toy it's been made out to be. If none of the food you eat is at it's peak, what difference does in make if it comes from New Jersey or New Caladonia?
The thing to keep in mind is that the problem is always the same: How do we best deliver food to where most people live?
In the 18th and most of the 19th centuries, America was, essentially, a rural country. Most people grew or raised much or all of their own food. Commercial farms could be economically located near the towns and cities. So truck farming worked. Today we are, essentially, an urban country. Farms have to be further away to accomplish the same task. So the choices are: grow the food using a factory farm system, so it can be grown economically, or, grow it close to the cities, where it will carry a premium price that reflects the added costs of production.
Is locally grown produce actually better? Maybe so. But what the locovores do is concentrate on the benefits while avoiding the elitist nature of such produce. The fact is, locally grown is expensive; and no amount of demand is going to change that except to drive prices even higher. Which means it's beyond the budgets of most of us. How many poor people do you see at farmers markets?).
Everything is a trade off. All I've ever argued is that the realities of those trade-offs be recognized. And that's something most locovores fail to do.
The other reality is that not everything can be produced locally. I'm not just talking about exotic, out-of-season fruits and veggies. As I noted above, salt is rarely a locally produced item. But it's essential for health and well-being. And, the fact is, most people do waht to buy tomatoes in February. We live in a world where doing-without isn't a viable choice for most people.
Much of this reminds me of the macrobiotic proponents of the 1960s. That, too, was based on principles that included only eating locally grown, in-season, foods. Except the mainstay of the diet was rice. Uh, huh. I was living in Boston at the time, and I can guarantee you there was no locally grown rice. But that didn't deter any of the macrobiotic soapboxers.