My xfinity cable modem apparently has a bluetooth beacon in it that is connected to the Tile network. One must dive into the settings to be able to turn it off (defaults to on) -- if you even know it's there to begin with (which I didn't at first).
If someone wanted to learn my home address, all they had to do was plant a Tile on me and they would have learned where I live the second I retuned home.
And if my xfinity cable modem has that in it and I didn't know about it, guess how many others' have it too...