[gkoberger]

There are actually no Walmarts in San Francisco. However that doesn't answer the root of your question; there are similar jobs (target, dishwashers, supermarkets, etc). Most would live in the east bay, sunset or South Bay -- about 25 minutes east, west or south of SF, respectively.

As to your first point, 5th Ave is smaller, but also more expensive. SF is bigger, but relatively cheaper. It's a sliding scale; both driven by scarcity of land compared to desirability.

[sentenza]

Wow, I didn't know that. Being from Europe and having only visited the US once (East Coast), I had the impression they were everywhere.

New York has a working mass transit system, though. For poor people this makes the world of a difference. I remember that, when I lived in Madrid a few years back, I was impressed by how fast you could go _everywhere_ in that city with the subway alone. A cross-town morning commute in that 3Mil Juggernaut took about as long as the cross-town car-commute in a less developed 130K city I had lived in before.

[TheCoelacanth]

They're much less common in urban areas because of the enormous cost of real estate that would be necessary for a store that large.