So I was curious about this. If you look at games in South Australia and Western Australia this year, there are
Four SA umpires (Fleer, DeBoy, Hay and Schmitt)
Five WA umpires (Dalgleish, Farmer, Margetts, Rosebury and Williamson)
If you go game by game in Adelaide and Perth
Round 1 Adelaide had 0 SA umpires
Round 1 Fremantle had 2 WA umpires
Round 2 Port Adelaide had 1 SA umpire
Round 2 West Coast had 0 WA umpires
Round 3 Showdown had 0 SA umpires
Round 3 Fremantle had 1 WA umpire
Round 4 Adelaide had 2 SA umpires
Round 4 West Coast had 1 WA umpire
Round 5 Port Adelaide had 0 SA umpires
Round 5 Fremantle had 0 WA umpires
Round 6 Adelaide had 0 SA umpires
Round 6 Derby had 2 WA umpires
So in 12 games, half had no local umpires, 3 had one, 3 had two, and none used only local umpires.
27 out of 36, or 75% of umpires were flown interstate to umpire in these matches. It doesn't seem like the AFL being unwilling to fly umpires interstate is a theory that holds in reality. But these figures are only for this year and may not continue as the year progresses.
Incidentally our Free Kick differential has worsened the more WA umpires are added..
I'm sure some of the interstate umpires grew up as WC supporters. Your supporter base is more wide spread than WA and is actually very strong in Victoria from memory?