Termite mounds are quite common in the outback, but not ubiquitous. You can drive for 100 km with them everywhere and then another 100 with none. At one of the rest areas, I saw how they formed.
At this place I saw them form on blades of grass. They also form on boulders, street signs and metal posts. Oddly, they never seem to form on dead wood.
From the simple beginnings, they seem to grow organically.