While Big Brother is tracking your every movement throughout the country using your cell phone, Little Brother is using your phone's wifi MAC address to track your every movement throughout their big box store.
Thousands of customer interactions a day are logged and uploaded to the databases of third-party companies that specialize in retail analytics. Estimates vary as to how big this industry is, but according to Polonetsky, nine major players account for the vast majority of tracking activity. Others estimate there could be as many as 40 major and minor firms.
I would wager that pretty much every national/international chain store you go into has this setup. Its just too juicy for them to pass up. Here's something hilarious from the article though:
In general, no personally identifiable information can be gathered this way, says Stillman Bradish, co-founder of The Wireless Registry, a D.C.-based start-up that designs ways for consumers to opt out of the tracking. But, he added, as with any type of metadata, it's easily possible to cross-reference it with other forms of public or commercial information. The resulting data slurry can help firms build detailed profiles of consumers, even if the consumers themselves remain anonymous.
You gave them your credit card AND your store loyalty card, you think they can't match that up with their MACdaddy database? Please.
How to beat this? Leave your phone in the car. In a box, just to be sure. And pay cash. They hate that.