Granted, it's local to AU which makes it small fry on a worldwide data black market scale.
Medicare cards are only worth 25 points in the 100-point check. You must present one of the "primary" 70-point documents: birth certificate, birth card, citizenship certificate, current or recently-expired passport, diplomatic or refugee papers.
Then you will need another form of identification, on top of the primary and medicare, to pass 100 points.
I think you're right though. All the people that make the most money from having health data could just lobby governments for access or just ask their customers for it.
One of the uk tabloids paid a lot for access to the medical records of Ian Brady (a notorious child serial killer)