[CRConrad]

But anyone who has your e-mail address -- a semi-public identifier, like your name or Facebook page -- can send you an e-mail. Is that also a "huge breach of [your] privacy"?

Is addressing you by name when one bumps into you on the street -- "Hey, Junky, did you hear about..." -- also a "huge breach of [your] privacy"?

That was the GP's question: How is this (targeted FB ad) any more a "huge breach of [your] privacy" than sending you an e-mail? (Or, my addition, than talking to you in the street?)

A weird and hugely convoluted way of talking to you, yes -- compared to, say, just posting a comment on your FB "wall" (do they still call it that?) -- but still: Just a way of talking to you, like e-mail or a Facebook wall posting.