BunnySlip.
While that may be entirely true in California, I have had an earthquake rider in Missouri on two properties (one within 120 mi of New Madrid) and in Arizona and the rider is not prohibitive.
I’m not surprised.
But you are not assured that you will experience a catastrophic earthquake in your lifetime. Your area is not know for killer earthquakes, hence your low premiums. For all of my 68 years, that has been drilled into me, that the “big one” is coming.
I draw some assurance that my California farming family emigrated from Germany in the mid-1800s, yet none have been injured in an earthquake.