The problem was one of the airlines own making. They wanted to screw the passenger by charging them to check bags in, then they found that people would just carry it onboard so the passengers were screwing with the airlines OTP. Now its back to the airline by screwing the passenger again by charging them for excess weight with the carry on bags. Weight is much easier to measure than the size of a bag if you are looking for the logic. When you have 220 pax coming back from the Goldie or even just SYD-MEL it was creating all sorts of problem with the amount of carry on baggage and where to stow it. At least the travelling public is learning and there are no longer any calls from the cabin "can we get ground staff to put this bag underneath".