I don't know, but I guess we're about to find out. People like the Chippewa/Ojibway lived on Mackinac Island in the past and supported themselves with a local economy, and white settlers lived in Northen Michigan long before cars were invented - in fact Sault Ste Marie, Michigan, not far from Mackinac Island, is something like the third oldest (European settled) city in the USA.

One of the problems with a heavily subsidized transportation system is that local production of basic commodities gets undermined by goods produced at a distance and transported in bulk. People have lost the habit and skill of growing their own food locally or putting up preserves, because they can get Florida oranges or Chilean apples year round. As fuel gets expensive, we'll pay a higher price for goods transported over a long distance, and we'll see a return to more local production, not just of food, but of many day-to-day items.