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Amazon's Just Walk Out technology relies on hundreds of workers in India watching you shop
(www.businessinsider.com)
This is a most excellent place for technology news and articles.
What ever happened to doing this with UHF RFID? Getting the cost of the individual chips down was always just a matter of scaling production.
They weren't just tracking what you bought. They wanted to track what you looked at and for how long, to learn what packaging worked best.