They don’t use facial recognition for that, just proximity sensors / BLE sensors. I installed about 4,000 of the BLE sensors in a hospital in Indiana last year as they had contracted to develop a phone app (Apple IOS and Android) to include location detection, way-finding, and points of interest throughout the hospital complex. It was pretty neat - but doesn’t do “facial” profiling, it does do “device” profiling, because it knows the MAC address of your device as it travels through the map, and moves you along your route.
Even if your device is not ‘discoverable’ for Bluetooth? Or does ‘discoverable’ only mean your device is open for pairing?
Yet more reason why I turn off wifi and location services except when I am actively using them. I've had apps refuse to install when I wouldn't allow them permission for location services.
Does an app interfacing with a bluetooth thermometer need my location? Nope so it doesn't get to run and gets a bad rating on Amazon.