Earlier quoted context omitted.
Assuming here you consider the users giving up their privacy as the primary product being sold in maps.
This seems wrong. I don't think the average business owner has the capability to reverse engineer the anonymous tokens that represent hash IDs. Also, it's good to go in and reset that occasionally with Google. I gave up on it and switched to apple, tho. Far as I can tell, they don't ever sell that info, even in anonymous hash # form. I'm happy to be proven wrong other than "wHy wOuLd yOu tRuSt aPPle?" .
https://en.m.wikipedia.org/wiki/Data_re-identification
That said:
https://en.m.wikipedia.org/wiki/Differential_privacy
However it wasn’t clear how high quality the differential privacy algorithm was or if it was attackable. But the nefariousness of its use against groups and demographics was fairly apparent.