In China: Smile to Pay

Seeming to be expanding in China.   Payment here, but to what degree also product recognition and tallying?

Smile-to-Pay: Chinese Shoppers Turn to Facial Payment Technology  in the Guardian

China is embracing facial payment technology, which allows consumers to purchase goods simply by posing in front of point-of-sale (POS) machines equipped with cameras after linking an image of their face to a digital payment system or bank account. Similar facial recognition software is already widely used by the government to monitor citizens, although authorities have been criticized for using it to crack down on dissent. Despite concerns over data security and privacy, many consumers seem unfazed by facial payment technology. Alipay—the financial arm of Alibaba—already has facial payment devices in place in 100 Chinese cities. ... "