There might not be gasoline for gangs to travel on after a few months. They’ll have to move on foot like the rest of us. The further you are out of a major city, the likelier it is you won’t see most of the hungry mobs. The ones you DO see will likely be the most motivated–and most dangerous. I downloaded a book some years ago written by a man who survived an economic crash in a South American country–Argentina, perhaps. He said the same thing about farms. The gangs would wait in the treelines to snipe the male members of the household, then move in to enjoy the females and children and live on the farm until its resources were gone, then kill anyone left, burn the house and move on.