There’s an old Doonesbury cartoon about the knucklehead journalist Roland Burton Hedley. During a visit to the Walden commune, Zonker convinces Hedley, among other things, that the Walden commune’s lilac bush is a marijuana plant and that Hedley can trust him because he gives his word that he represents a national trend. So Hedley writes a big Time cover story about the resurgence of the hippie movement, relying solely on Zonker’s assertions.
The web is far enough along that most topical areas have enough eyeballs on them to keep the BS artists in line, but there are still venues where the level of participation is low enough that a few determined purveyors of misinformation could plant their own row of lilac bushes and sell them to us as pot plants. I can’t point to any specific examples, but I bet it wouldn’t take a whole lot of sleuthing to identify Amazon book authors, wonder-drug sales people, and black-hat SEOs who are essentially doing this.