Yeah, I wouldn't be surprised if anti-virus companies did that. It's a great way to boost their bottom line. It's why any time there's a hack or a breach, Norton trumpets it from the rooftops so they can get more people upset and scared. My dad always said all marketing was based on fear or lust. They're either trying to make you afraid so you buy their product to protect yourself, or they're trying to make you feel inadequate so that you buy their product to make yourself feel better. (i.e. lusting after a car and the prestige that driving it will bring you.)
On the Big Bang Theory (tv show) one of the characters works for a pharmaceutical company in the research division and she jokes about creating and curing a disease. It wouldn't shock me if someone found out that some of these new diseases that we're encountering were made so big pharma could sell a "treatment." They definitely wouldn't sell the cure!