OK, I am stuck working in San Francisco for a while. SF has many “free press” type newspapers. They have various ads in the back and some of the ads have telephone numbers that go “*82 415-555-1212”. Most, but not all of these ads are for various “personal services”. 
I have no interest in calling them, but they make me wonder none the less, and I have asked a few dudes and no one knows.
*82 is what you dial to “unblock” your phone number so that it shows up on caller ID.
For example, my sister’s phone service automatically blocks calls from private (i.e., blocked) phone numbers. So, because I have a private number, I have to hit *82 before I call her, or I will get a nasty recording telling me to unblock or not bother calling her again.
In the situation you mention, I would assume it’s to cut down on prank calls. (Serious offers only, so to speak ;).)
If your number is unblocked, what do you dial to block it? (I guess ours is unblocked. Our daughter knows it’s us when we call her.)
“un” block it? I’m not quite sure I take your meaning, sir.
Mmmuuuaaaahhahahahahhahaha!
*67
TY