That is a rather bold statement saying that "hackers" work for money, considering that in doing so, they are violating about 8 laws, the companies included. Some of these laws are federal, which can lead to life in prison.
I would say some people find joy in causing the downfall of more or less half the world's computer systems.. It would almost appear that Linux and/or Macintosh users would be behind it (as they tend to hate the Bill Gates Devil). But then, that too is a bold statement that needs not bare repeating.
Is is possible Microsoft itself is making the viruses? In order to flush out pirates? Again, this theory is far fetched and improbable.
All in all, I think it's just someone with a society complex who wants people to know he (or she) is better than they are by causing their computer to do even more annoying things than it already does.