It is a massive rip off by the motoring bodies across Australia.
I have taken one in the past but never needed. I travel to Europe most years and hire cars in many countries.
However a mate who also heads to Europe at least once a year was asked 18 months ago with one company on a booking he had. Had to find another company to renty off at FCO. I will take one next year while in Greece, Italy, Germany and Spain.