[majormajor]

(Coastal) California suburbs and small towns tend to be much denser than suburbs in most of the rest of the country. Most of LA city proper is considered suburban, but it also averages out to something like 8K people/sq mile. Even somewhere more suburban like Anaheim clocks in at 6.6K. Compare that with Dallas (3.6).

I would've expected those density gains to be somewhat more offset by the worse fuel efficiency of sitting in LA traffic, though... but on the other hand, much of the LA area has far lower heating/cooling costs than almost anywhere else in the country.