I've seen brushfires jump a highway that's two lanes each way, wide shoulders left and right in both directions, with a 50ft wide grass median. We're talking about a 200ft wide are it jumped, and the fire I saw wasn't anywhere near as big. The energy they release is incredible, and what it wants to burn WILL burn. Once a fire like that gets going, all you can do is TRY and steer it, only mother nature can put it out.
There are ways to mitigate it of course, such as material choices, but even with proper precautions those houses most likely would have still burned. I don't recall if there is any seisemic reason they don't use more concrete/brick construction out there, but I do recall seeing quite a lot of tile roofing last time I was in Colorado Springs. They also do a lot of 'veriscaping', due to the naturally dry conditions, meaning they do rock gardens and such instead of grass lawns. Laws are you can't irrigate or water your lawn, unless you have 35 acres, then you are allowed to irrigate ONE acre.