Tracking is provided to allow for the convenience where available for the sender and the intended recipient to keep abreast of the articles movements. Australia Post advertises that the scans are not compulsory except for the lodgment scans however in most instances scans do occur.

They do? Is that person sure? :^O Please ask them to advise where they advertise that tracking may or may not actually occur, because on their "simply send it" page, it says

No matter what speed or size you choose, every parcel is tracked.

There's no little asterisk denoting disclaimers, with a statement anywhere on that page saying "actually, we don't promise that every parcel is tracked..."

There's a little link for the full terms and conditions, and I can find no such statement there, either.