And, if you do your homework and read the link you would know by now you should avoid it as the plague.
But again link:
Mac Virus/Malware FAQ - Mac Guides
Sorry buddy, but ... ;-) Besides being arrogant, you don't even know what i am running on my system. Even as a mac user, you might receive a virus for windows, and many of us are running multiple VMs including windows (i'm running Windows 7,8, various Linux VMs - for example). So, i receive my email via Mac. i save a file to disk, and i open it in windows. - Of course i need a virus scanner and of course i want it to be running natively on OSX.
So, get a little more relaxed, less arrogant, and *think* *twice* before being so arrogant.
Just to let you know, i was very much into anti-virus development many years ago and i am an x86 assembler master, you don't have to explain me what is possible and what's not.
another scenario: even a mac user can receive an email with infected code, spread it over to some friends who actually are running windows. there is multiple reasons why wou will want to fight malicious code as early as possible.
p.s. from your link: "as a Mac user, your chances of being affected by a virus, trojan or other malware are extremely slim".
slim != zero.
and yes, a virus scanner is never perfect. will never be. we all know that. but you got the choice between zero protection, and some protection.