Recently, I overheard by chance some technically savvy guys saying that when you accept the terms of service in order to use the "free" WiFi at Starbucks (which you pay for when you buy some coffee), the popup window actually performs an HTTP operation that sends the computer's WiFi MAC address in the URL in an HTTP GET request to the service that Starbucks has contracted with, e.g. "GoogleStarbucks". Why do they do that? Are they actually recording all of the customers packet traffic? If so that is a serious privacy violation!
I heard this happens on a Macbook, but I assume iPhones as well and I am curious if Windows and Linux users can confirm here in this forum that it happens to them too.
Concern #1: That Starbucks is recording all traffic for some MAC addresses.
Concern #2: That Starbucks is sending the MAC address to some services e.g. if you log in to an anonymous email account, it's provided somehow.
Concern #4: That Starbucks is recording my daily patterns e.g. which Starbuckses I go to and when, and selling it to the highest bidder.
Concern #5: Retailers are sharing this information, so that if someone with a given MAC goes to Starbucks, that same MAC is tracked in other stores that the shopper happens to pass by e.g. in a mall.