Why do CADETS get priority over direct entry pilots with real experience (not ICUS or P3 time) and get priority.
In these specific circumstances it's because these cadets were identified by Qantas more than 6 years ago as being the type of pilot they wanted. They were tapped on the shoulder back then as being suitable, went through all the selection process, were crutinised whilst doing their ab initio training far more than their non cadet colleagues and when graduating were told that Qantas hoped to employ them ASAP.
So here we are 6-8 years later from when they went through the selection process and subsequent training, scrutiny and graduation, and you're asking why they should get priority over someone who hasn't been through that process at all and is a complete unknown to Qantas?
In general terms regarding cadetships, well that's a topic that's been done to death on this forum. In 20 years I reckon the various levels of government will have essentially killed off GA and the various cadetships will be the new pathway into airlines.