Why would potential EU pax choose to fly to/via Darwin when they can 1 stop from virtually any EU city, via DXB, to Mel/Syd/Per/Bne multiple times/day?
Cheap tickets. Passengers on Jetstar already fly SYD/MEL to BLI/SIN/SGN via DRW, often with several hours on the ground at DRW at some ungodly hour. So I suppose there may be a market there, even with the stopovers, if it's cheap enough.