Did you know that the US Mail Service takes pictures of the front and back of every piece of mail that goes through the USPS system?
And they keep that information.
They know every single person you send a piece of physical mail to, and every single person who sends a piece of physical mail to you.
I am NOT kidding.
True. They can even send you an email everyday with pictures of the mail you are going to receive that day. Privacy is pretty dead everywhere.