I fail to see how hiring fake blog commenters has anything to do with SEO. That tactic will certainly not rocket a web site to the top of the rankings. While it is clearly unethical to hire fake commenters, it is just not an effective SEO method. I would agree that any company who offers services like that and calling it SEO is something that would disgust me as well, because is just not SEO. I've always seen fake comments and fake reviews as a tactic used by weak sites to make their sites look popular. That would make it a marketing technique, but not SEO.
Perhaps the real problem is that the author of the article does not really know much about SEO. Read his profile. There is no indication that he has any experience with SEO or Internet marketing. He is a university teacher.
This reminds me of an article that John C. Dvorak from PC Magazine wrote a few years ago where he also blasted SEO as a scam. He went on to outline the advice that he had been given by a "friend" who claimed to know SEO. He ultimately implemented that advice on his web site and traffic plummeted. That was his proof that SEO did not work. No SEO professional would have given him that advice because what happened to his site as a result was predictable. He followed bad advice from someone who thought he knew something about SEO, but obviously did not.
While there is no question that there are a lot of unethical SEO companies out there and a lot of legitimate complaints about SEO scams, articles like this written about non-issues by people who know very little about this topic are annoying to anyone who runs a legitimate SEO company.
"It's inexcusable for scientists to torture animals; let them make their experiments on journalists and politicians." -Henrik Ibsen