To offer it a slightly different tangent and speaking as a rugby referee, which I've been for over twenty years. I got into reffing when playing wasn't an option anymore, plus as a PE teacher, I worked Saturdays and had to referee school matches. The overwhelming majority of rugby referees across the country are of this nature, ie retired from playing but want to stay involved in the game and put back in. The real point to note however is that those who referee level 3 and above (National League 1, Championship and Premiership) will all be 20-35ish and have committed to refereeing above playing at a young age, been fast-tracked through federation and trained accordingly. If you haven't made level 4 by about age 27, you most probably aren't going to make it, hence why the standard of refereeing is arguably much higher than Football and, by and large, more consistent (unless they're French, but that's another story).