In Japan at least, before automated facial recognition, cashiers recorded buyer demographics by hand. I would think other places do it too. Edit: Here is what the buttons look like. Gender and age. https://image.slidesharecdn.com/hvc-c-android-prototype20141...
Facial recognition is a unique identifier but cashiers have access to almost nothing they can record... [Edit] What was it?
Edit: clarified that I am asking about the history here, what information was manually collected by cashiers as parent stated