At least 49 billboards have cameras that count cars by recognising their number plates, but they do not identify their owners, according to owner Lumo.
Meanwhile, Westfield shopping malls have 126 SmartScreens that can detect faces and even gauge what mood a person is in - but not who they are.
The advertising, tech and retail companies at the leading edge of the digital expansion said they were not gathering or processing any personal data, or it was all anonymised, and that they followed all privacy laws.
“The business has no interest in the movement of individuals,” said Canterbury’s Go Media, which has digital billboards in the three main centres.
“Rather, Out-Of-Home [OOH advertising] has always been used to deliver advertisers’ marketing messages to large volumes of audiences.”
Go Media used a mobile GPS platform that gave it “down to the hour” data for each digital screen about “customers’ real-world behaviours, brand affinities and purchase habits” - but none of that had identifiers attached, it said.
The GPS platform is from Australian firm Landmarks ID.
It has a deal to access the location data from the phone apps of more than 80,000 members of the leading consumer loyalty scheme, AA Smartfuel.
Members were only enrolled if they explicitly opted in, AA Smartfuel said.
- RNZ