University of Waterloo found covertly using facial recognition 

Students at the University of Waterloo in Canada discovered that 'intelligent' vending machines on campus were using facial recognition without their knowledge.

The facial recognition capability was accidentally found by a student after an error message appeared on a screen of one of the M&M-branded vending machines. Students then began to cover a tiny hole apparently concealing the camera with chewing gum and sticky notes. 

They also discovered online a a brochure for the machines which revealed that they were installed with a 'demographic sensor' allowing them to calculate the age and gender of anyone that approaches and make 'AI-powered product recommendations.'

Invenda said the vending machines do not store or transmit personally identifiable imagery. However, the university demanded the software was disabled and machines removed from campus.