California has pretty bad fires on a regular basis, and has learned to deal with them fairly effectively. There have been a few exceptions, but they are rare.

I think a key factor, not surprisingly, is the relative affluence of the populations. In California, everyone has a car. You simply drive away from the flames, bypassing the Red Cross and large animal shelters on the way to the motel/resort/friend's home of your choice. Shelters are typically underutilized. Even a very bad fire which guts a few hundred homes affects only a very small fraction of the population, hence there is no large scale disruption.

The Big One, properly situated, may well be a different story. A large earthquake, epicentered within a large urban population, might well result in something like Katrina. A close analogy of what might come would be the 1906 San Francisco earthquake. Apparently the death toll there was likely much higher than the heavily spun "official" count.