A couple of negative things about the multi registered rule.
I'm pretty sure there is a fee to do it, might be $50. So it's a bit of a money making scam from association really. If it's not there to make money then the association should drop the fee and allow clubs a maximum of multiple registered players from all age. Say maybe 5-6 players.

Im also thinking there used to be a rule where they had to be used by there all age team when any clashes occur? Not very ideal if your multi registering Saturday all age playerd