I don't think tracking people in store (already quite established, as you point out) was what the article was referring to. I understood it to mean that it's difficult to see if people are walking into your store because of something they saw online, and if so, what.
Seems like Google could do this quite easily. Provide a WiFi service that customers in-store would auto-sign into, that way they can tell if a customer visiting the store has been exposed to any mention of the shop online. I imagine only Google or Apple, or maybe Facebook, could do this because of the sheer amount of information they tend to have on peoples browsing history and location tracking ability.
Seems like Google could do this quite easily. Provide a WiFi service that customers in-store would auto-sign into, that way they can tell if a customer visiting the store has been exposed to any mention of the shop online. I imagine only Google or Apple, or maybe Facebook, could do this because of the sheer amount of information they tend to have on peoples browsing history and location tracking ability.