You could make the same argument about LoyceV in the Meta section and pushing his statistics site on users here. One might think there doesn't need to be a different topic for every single statistic listed on the site, but who really cares if people want to merit hunt by making lots of threads. If people want to spam threads I don't think there's any rules against it. At some point if it bothers people they will just hit the ignore button. I only wish this site had better block options, where when you blocked someone they aren't able to see your posts and vice versa, instead of them just being ignored and greyed out.
The key difference with this case; is they aren't directly copying the content from their website, and pasting it here. Whereas, the quoted user above was doing exactly that, then providing the source, but the intention of posting was mainly for the purpose of advertising. There was no additional content or thoughts or anything. Copy contents of website, paste, probably never return back to the thread, and instead copy another of their articles, and repeat.
I do think it's generally good practice to keep somewhat related threads into one though. So, I do get your point there.