hardcore people always make the false assumption that only hardcore people are buying the hardcore games.
like you said all hardcore people know of the games due to interent, but that doesn't equate to not needing to advertise. If halo 3 or call of duty didnt' advertise it would be lucky to have half the sales it has.
and bringing up madworld ever in examples is just retarded, that game is not ever going to sell millions on any format.