[omgbananas]

Roving gangs won't stick to cities, they will branch out and then that family alone on their homestead won't stand a chance. However if they are in a neighborhood and work together with their neighbors, then they have a fighting chance.

[brandall10]

That's near term thinking. Longer term thinking had the # of people who were living sustainably OTG to be a vastly small minority of the populace, hence everyone aside from immediate family members were your enemies.

In regards to population density, the further groups had to travel on limited resources the more dispersed and weaker they would be, and in turn the amount of resources available would be more dispersed relative to lack to nearby neighbors, all of which would be reasonably well protected.

Basically, you want to be relatively well fortified slim-pickings that are hard to reach.

[blacksmith_tb]

That seems unlikely - why try and pillage the relatively sparse countryside when so many more resources are concentrated in the cities? I suppose if we're talking the end of civilization then eventually, sure, but who wants to survive that anyhow?