LOL! I'd never seen those, either. Must not be a priority in my region, or I haven't been to a Walgreens recently. But, here's the reason:
> front-facing sensors used to anonymously track shoppers interacting with the platform
From my (albeit limited) experience with tech platforms like this, it probably is anonymous - but they're scary good at identifying your age and gender, and what you look at before you buy. That's the data they're immediately after.
Of course, they've probably already built a "shadow" profile of you based on your mobile phone identity, so they could cross-reference that if they cared to, and then a loyalty profile they could connect to that. So, yeah... The fridge data is technically anonymous, but, you know, data can be connected together in all sorts of ways. Privacy is dead.