> makes me wonder if people in a Starbucks get ads intended profiled against other customers)

unlikey, at your home location, usually it is just the same few people all the time.

At a coffee shop there might a couple of the same people every time, but also lots of other random people. So would be easy to ID home location / office location / public space location.

Or perhaps they know the location is a coffee shop from their facebook location ID.

but they will know somehow