The thing you really forget about the deplorable land use and development patterns in southern California (and the Southwest more generally) until you come back out here is how goddamn nice the weather is, a fact that takes the situation out of the realm of farce and into tragedy. You know what a good place to never walk anywhere would be? Boston or Chicago in the winter. Or maybe DC or New York in the summer. That's some nasty weather to be walking around in.
But LA would be a great place to walk or ride a bike to work all year 'round. But it's our bad weather belt that has the walkable cities, and our sunny and temperate all the time region that barely has sidewalks.