Re: The fundamental thing is, do I get to say "no thanks?"
I never got a chance to say "no thanks". I don't recall ever communicating with them.
I think they just lie. They have their own way of finding out who you are, perhaps through connections I have in common, and then they take advantage of them.
Like most spam and junk mail, you don't normally get the opportunity to politely decline. It just shows up.