i think its softer than that - encouraging / communicating etc. Once it gets going it's self perpetuating, but can be hard to get goingIts also horses to water.
back in the day when I was a CCC, I also took on the mantle of CRefC as it was same same but different.
Getting volunteer dads onto the bare minimum coaching courses, let alone any knowledge/ability development stuff, was the devils own job. Let alone then getting them also onto any ref development.
So Im totally with CR's idea... but my admittedly very limited experience in this area doesn't fill me with much hope I'm afraid.
I suppose it could come down not to a "don't take the courses, then there are no games permitted" is fine in principle - but who potentially actually misses out here? The players, whose "fault" it is not.
Also I think the set of parents who might want to coach are not the same as the set of parents who might want to ref (of course there is overlap). so it's finding them