Yeah, i wasn't trying to say that it was common but it is possible. Good example is Andre Villas Boas. Never played, managed Tottenham and Chelsea (kinda poorly, admittedly). Plus, even with if you don't make it to those heady heights in football, there are plenty of paid jobs for a middling or low level coach. Shit, even Bristol City FC had paid coaches and they were third division at the time.
Edit: my point is that no reasonable person would try to become a coach if there aren't paid positions available. Which is pretty obviously why there are no rugby coaches in Australia.
That's the big problem with rugby being a relatively small sport in Australia.
There aren't really the pathways to become an elite coach in Australia although we are working on changing that (which is also attracting plenty of criticism).
Look at every elite professional Australian coach in the last decade or so. They all have spent significant time in Europe. Cheika, McKenzie, Taylor etc. That essentially has been the only viable pathway to actually becoming a good coach.
There's heaps of criticism about the coaches who haven't spent a lot of time offshore getting promoted from assistant roles/NRC head coach roles such as Nick Stiles, Dan McKellar etc. The reality though is that we need this pathway. I don't think it is a good plan to say that the only way you can become a decent rugby coach in Australia is to leave the place.
We need to be create the right structures so coaches can improve through various levels and work their way up to being quality professional coaches. It's certainly going to take some time to mature but I think it's the right way to proceed.