you drive around, walk around with your phone.
they look for 2 places where you spend the most time,
one being work, and one being home.
they than look at what you do, as in where you go, and sell that info to places.
lets say that you drive 20 miles to a redbox, for me i don't, but thats how far away the nearest one is.
they sell the info, and based on that info alone, they put up a red box within walking distance of your home.
that's what this kind of selling can get you, and in all honesty i don't mind. i mean they aren't selling it to people who send you an advertisement specifically. they sell it to people for strategy, like where to put the next store.