While the ratio of guns/people is much higher in the countryside, the absolute number of guns in a big city is orders of magnitude higher than the absolute number of guns in any rural county. Even if there were no guns in the city, a mob of desparate people will charge a smaller number of better-armed people if starvation is the only other alternative. Also, rural populations are, by definition, spread out, making it easy for large mobs of looters to pick them off one homestead at a time. Those well-armed country folk aren't going to fare so well unless they are really far from the nearest big city.
>I'd like to think that a new system of logistics would evolve very quickly after a total financial disaster, so long as the food supplies didn't get so low that peoples' low blood sugar diminishes their ability to control their anger.
I'd like to think so, too. In areas with lower population density, it will probably work out that way, in large measure because it is possible in a small enough community to know almost everyone, making trust and barter a lot easier. In cities, where trade relies on cash because there are too many strangers, and where the logistical system is much more complex, I don't think it's likely for a viable alternative to evolve quickly enough to prevent mass starvation and the accompanying violence.
While we're on the subject of apocalyptic scenarios, it's important to remember that there is an abundance of guns in the countryside, so any of us "city folk" hoping to loot some tasty country cooking are in for a different sort of treat.
An event like this would probably result in a death toll comparable to a widespread nuclear strike, and would equally destroy the nation as a functioning political and social entity.
I'd like to think that a new system of logistics would evolve very quickly after a total financial disaster, so long as the food supplies didn't get so low that peoples' low blood sugar diminishes their ability to control their anger.