Sainsbury's

Sainsbury's is a notable user of Facewatch. This means that in certain branches, the cameras perform facial recognition on every customer in the shop. Sainsbury's have announced their intent to accelerate the aggressive roll-out of this technology. Legally, these shops are required to have a notice in the window disclosing the use of facial recognition, but these signs can be discreet and easy to miss.
They also anticipate customers being unhappy about this by putting some sob story poster next to it in the window with the title "We must put safety first in our stores", trying to convince normies that the mass surveillance machine is actually a good thing.
This is not a complete list! If you know of a branch using facial recognition that is not listed here, please add it!
Known Locations
Bath Oldfield Park
Confirmed in official announcement
https://corporate.sainsburys.co.uk/purpose-in-action/we-must-put-safety-first-in-our-stores/
Camden
Confirmed in official announcement
https://corporate.sainsburys.co.uk/purpose-in-action/we-must-put-safety-first-in-our-stores/
Dalston
Confirmed in official announcement
https://corporate.sainsburys.co.uk/purpose-in-action/we-must-put-safety-first-in-our-stores/
Deptford
The Sainsbury's Local right outside of Deptford railway station. Spotted by User:Chalk.
(TODO: Take photos and upload here. Signs are not yet visible on Google Street View.)
East Dulwich
This branch has received a lot of news coverage, as one of the first locations that Sainsbury's have been performing facial recognition trials. A customer here was ejected from the branch after being misidentified as a shoplifter, leading to Sainsbury's pausing facial recognition in this specific branch (but only temporarily).
Elephant and Castle
This branch uses Facewatch and has received news coverage about an innocent customer being wrongfully identified as a criminal.
https://www.bbc.co.uk/news/articles/c0lxdn4w2g3o
Ladbroke Grove
Confirmed in official announcement
https://corporate.sainsburys.co.uk/purpose-in-action/we-must-put-safety-first-in-our-stores/
Sydenham
Confirmed in official announcement
https://corporate.sainsburys.co.uk/purpose-in-action/we-must-put-safety-first-in-our-stores/
Whitechapel
Confirmed in official announcement
https://corporate.sainsburys.co.uk/purpose-in-action/we-must-put-safety-first-in-our-stores/