this is so wrong. Really. Imagine that: you go buy a car, and a few month later the manufacturer calls you and offers you in fact working brakes. Indeed working, no need to bother about stopping your vehicle, finally a safe ride. 

And it's just no different selling an anti-virus package for your own Operating System. It's naughty to offer it as a seperate product, as it simply provides a functionality that everybody expects from an operating system. An operating system is simply a means to run you programs, solve problems etc., but the users shouldn't have to care about viruses or anything alike. And because it seems to me that Microsoft messed with users habits long enough now, many people finally accept that Windows needs a Virus Scanner, because it's vulnerable by design and incapable of handling threats reliably on its own. Sad but true, the majority of users is still unaware of better-working alternate operating systems. Ubuntu runs just fine on my mothers notebook. Mac OS everywhere else here. And everybody is happy. And we are not buying Anti-Virus Packages. Score.