In current flying practice on type, they are for CofG. If you had the SS-11 fit or have the dual instrument panel, not required, else, solo and under 9st (ish) and depending on fuel load, they would be required. Next time I’m in the Hangar, I’ll take a photo of the CofG chart to demonstrate. You’ll note the RAN Scout has the sand filters fitted which will bring the CofG aft.
MR