And another thing....
The quality of any league relies on its depth. If a bunch of D4 clubs went belly up, there wouldn't be any relegation in D3? Then they would have nothing to play for either... The league needs to support the teams at the wrong end of the table... allow us to grow by:
reducing the association fees for D4 clubs (especially as we're travelling more than anyone else, get crappier umpires, play on crappier grounds and hence sustain more injuries. We ask for less membership money, can't sell a footy record for anything other than $0, etc... etc...)
The fees are reduced they become more expensive as you progress through the grades.