TL;DR

ID scanning is becoming a more common requirement to access bars and clubs in Australia (and worldwide). A company called ScanTek is used in over 1,000 clubs in Aus and provides tools such as biometric-matching someone's face to an ID, detecting fake IDs, flagging people and sharing data with other venues automatically

As well as verifying ages, ScanTek boasts "collect marketing information from IDs and drivers licences, which business owners can use to target specific demographics with promotions" on its website in a pitch to business owners. Though they claim to not share any of this with third parties

Australia's privacy laws are vague, don't specify what can be collected and how it must be stored, and only say that companies shouldn't keep data for longer than is "reasonable"