Okay, sorry, maybe.
I suppose the presumption that macuser=clever person who doesn't install bad programs, winteluser=person who breaks system while surfing on a daily basis isn't really valid.
I'm not sure a malware scanner and an AV package should really be one and the same, or you'll start heading for the levels of security kludge bloat that plague windows. That's different though.
Maybe once, when pirate mac software was a rarity this was genuinely a non-issue. Now, I suppose it's a ticking timebomb, but there's still the option to only install stuff you've paid for from a reputable source.
I've not really heard of any serious apple virus problems that didn't rely on social engineering though, but I have a feeling you want to tell me otherwise?