This is a fallacy. Cities can survive only because they are supported by the countryside where the food and other resources come from. In case of collapse, cities are the first to suffer. For example; this year was bad for potatoes and it is really hard to buy them. Countryside folks who have them, keep them for their own use. Potatoes are simply not for sale! If we amplify this example; people with crops will at least have something to eat while people in cities might starve.

So who will survive the apocalypse? People like the Amazon tribes are the safest bet, followed by people who live in small self-sustainable villages in mountains of Tibet, Ural, the Balkans, and don't have much connection with the civilisation already. They have to take care of themselves. They have survival skills.