None of these rumor mills are run by journalists. The ethics and rules real journalists live (and die) by don't apply. And if the baloney being passed off as facts don't pan out a year or two later, who's going to dig it up and complain?
It's all about the hits they get when people click on them.
I recently watched the movie Shattered Glass, about a rising star journalist, Phillip Glass, who fabricated articles for a respected publication in the 1990's. A person like Glass would probably have a blog today, (with a lot of blind followers eating up every word) with nobody fact checking or questioning the veracity of their work.