Can you fit a '69 Dodge Polara in a garage made for a Model T? Most of the Island That Time Forgot had long since been built up by the time it became clear the automobile was here to stay.
Because most houses on the island were built before 1920, most garages tend to be unsuitable for modern vehicles. Either they're tiny shacks like the one housing the Polara, or they're made for very narrow cars with sufficient ground clearance to get down a steep grade. You don't like it, buy a Model T… or park on the street. So that's the main reason we see so many interesting old cars parked on Alameda's streets; I'm sure most California cities are packed with such treasures, but they spend most of their time behind a (modern) garage's door.