As is shopping centre car parks in Australia are not busy enough this time of the year! Today at one shopping centre, several times I saw a court appointed sherif with lights flashing slowing moving past rows of cars checking number plates. If they find a plate that matches the computer system showing fines owed, the car is clamped.
While I understand governments want to collect their fines, they should not do it in such a way that disrupts retail, especially in a busy retail period! Click here and here for one of several stories showing this this really is a thing.
I agree that checking cars should not be used in areas likely to cause congestion. Automatic car detection and then clamping is not a recent thing. It has been in use in Vic at least since late 2011.
The other new technology that is appearing is electronic parking meters with a short range wireless. All the parking police do is drive down streets while their van uses the wireless connection to check the meters. If the meter is expired the car is automatically photographed and the number plate read. The next thing you know you have received a fine in the mail.