Here’s a simple experiment anyone can try:
Gather all of your smartphones and smart devices in one place.
Turn off all of the apps on your smartphones and smart devices. But leave them on.
Now start discussing a vacation to a place that you have never talked about going before, A place you have no intention of visiting, And a place that you have no desire to visit.
Now sit back and watch as the advertising comes in for hotels in that place, airlines to get you to that place, travel insurance, and et cetera.
And even though you were telling this information to your smart devices watch as the advertising comes in through the mail, youtube, email, and even on the telephone.
I have done a similar thing as well. About three years ago, I got into this conversation with a friend and his wife who thought I was a being a paranoid nutcase by saying all these devices constantly are listening in. He and his wife were in the room with the TV, computer and their cell phones. I said humor me, and began talking about the cat being sick and needing to find a good vet in the area to treat the sick cat (they don’t have a cat). They called me the next day to tell me that all their ads on the phone and computer were for pet meds, vet services, local vet clinics, etc.