swh -in employment terms, Singapore and Hong Kong are in no way considered to be the same region as Australia. Do you really expect Australian employees to be rewarded the same as HKG based? I doubt it.
In the "region", Jetstar are on par with other narrow body operators. Virgin Pacific, Virgin Blue, Jet Connect, Freedom, NJS, Skywest etc. None of these pay "almost twice as much" as Jetstar.
There are pilots "leaving" Singapore and Taiwan to move to Jetsar in Oz. Eva and Silkair have been a good source of crew. And they are certainly not moving to where the money is better. Perhaps they have other motives.