Your source in the marketing material of an IP camera manufacturer.
We research that space and I can guarantee that less than 0.1% of IP cameras have facial recognition built-in or running. These manufacturers, like Axis, whom you cite, would love for such capabilities but they are still very uncommon.
While I'm sure this is true (since the majority of IP cameras in the world are cheap things little more than webcams), do you have a number for retail stores specifically? I know many of the larger chains spend a lot of money on their cameras and movement detection and other intelligence has been onboard those for at least 15 years.