Truthfully, I know some of those recruiters personally. I don't hold it against them. They're paid terribly and their job is at risk if they don't get candidates.
I just be as polite as I can, but I hold them to their word.
I don't mean harassment by the recruiters, especially if it's the first contact. But surely the recruiting division has a database of people they've contacted and who asked not to be contacted again?