I really don't see what the problem is with this. Its been going on in the US and Europe for years and now Australian travellers have the opportunity to have a cheaper fare by 'selling' their baggage right. The problem will be if Jetstar do not portray the terms and conditions to the traveller to a comprehensible level. It will be a sh!tfight at the gate to the Jetstar staff when someone tries to sneak on a tea chest as carry on.