I'm sorry but I have to comment on this. My feeling is that you...

I'm sorry but I have to comment on this.

My feeling is that you probably misunderstood the point of the call. I have now been through two separate NBN connections so I know the drill.

My guess is that they called and offered to connect you to the NBN which may have required a field tech to visit if you're on the FTTP or HFC network (like I am). Whilst you wouldn't pay for the connection itself, it's likely you would have to pay for the modem/router to be shipped and maybe first months charge, hence the need for credit card details. It's actually very standard.

People often get their backs up when people call selling a service so I'd hazard a guess that you went in all guns blazing and when you misunderstood the service disconnection comment (probably along the lines of "everyone will need to move over to NBN eventually as all copper services will be cut in the future"), you decided to jump onto HC to air you grievance. What an odd thing to do...