I'm not an expert, but I have looked into some of the basics before and computer vision is really freaking hard to do very well. It's relatively easy to get a basic proof of concept up and running, but in a store you have people carrying shopping bags, people moving products and things around, employees going about their business, people pushing shopping carts around, and have kids running around. I'm sure this presents a considerable challenge to accurately track what's going on just by relying on analyzing video feeds without human intervention. In contrast, it's pretty much easier to just track WiFi signals.
As long as no personally identifying information such as a phone number or some sort of phone ID is gathered without a customer deliberately giving it to the company and tracking cookies aren't used without permission, I wouldn't think there's much of an issue here. I might even appreciate, with some kind of deliberate opt-in, seeing some coupons or sales info showing up on my phone when I'm spending 5-10 minutes in one single section of the store.
This is still a potential privacy issue if they're somehow using cookies or some other information to track people without their consent, but as it's presumably on private property this is a different kind of privacy issue than government spying.
> or some sort of phone ID is gathered without a customer deliberately giving it to the company
Chances are better than good that they're capturing your MAC address. While not necessarily unique, on cell phones, it's probably as good as in the vast majority of cases.
As long as no personally identifying information such as a phone number or some sort of phone ID is gathered without a customer deliberately giving it to the company and tracking cookies aren't used without permission, I wouldn't think there's much of an issue here. I might even appreciate, with some kind of deliberate opt-in, seeing some coupons or sales info showing up on my phone when I'm spending 5-10 minutes in one single section of the store.
This is still a potential privacy issue if they're somehow using cookies or some other information to track people without their consent, but as it's presumably on private property this is a different kind of privacy issue than government spying.