Why is that billboard smiling at you? Because it tracks your smartphone MAC address to advertise

[DisgustipatedinCA]

47. My original problem wasn't the ads, although I don't like them

My original problem was that you were trying to lord tech knowledge over someone else as a way to cudgel them into seeing your point of view, which missed the technical mark. As I insinuated in my first reply to you, the MAC alone will not get you John's browsing history. I said it would require hacking (we've covered that) or collusion on the part of the carrier (or manufacturer, but I didn't mention that on the first go). The 48-bit identifier that is the MAC address isn't where the problem lies. The problem lies with carriers willing to sell your privacy. The technologies used in cellular data will work just fine without having to expose data to advertisers as an unfortunate side effect. So you can't really accuse those who don't like this of being Luddites when the central question is not technological in nature, but is instead centered on profit versus privacy. Its detractors do have valid points.