Today´s world economy cannot be divided into independent sectors, it works like one big, organic worldwide cloud. Everything is related.One cannot find real shanty town in San Francisco, but Bay Area industry certainly has some influence over urban areas in developing economies worldwide.
So I believe, that San Francisco should have shanty town, although just a miniature one. In a shanty town spirit, it is built from reused material, mostly cartoon and it is situated at not habited spot of the city, raw, wild looking Corona Heights.