Sometimes this comes from well-intentioned people who aren't observant enough to notice what's unusual about the story. "So some rich lady fell down some stairs in her one-story house somehow and her gambling-addicted nephew inherits all her money. So basically, somebody died. Big deal. People die every day! There was a story just yesterday about a guy who had a heart attack during the Super Bowl. There's nothing new under the sun, folks. Death happens! I don't know why you're so shocked!"
That might be a bit extreme, but a lot of simple people can oversimplify a story so that in summary, of course it sounds like a cliche. A story about Gaddafi's excesses? "Oh, boy, a dictator being eccentric and insane, like we haven't heard that before." Only when he's actually in the process of being overthrown, and these things are directly fueling the anger of the people overthrowing him, it seems kind of relevant what specific things are riling them up.
AP, via The Guardian
Like this stupid couch he bought for his daughter.
But worse than the well-intentioned people are the people who think that posting news stories is some kind of contest where you try to shock other people, and the least shocked person is the "winner." They see being shocked or disturbed or surprised as an admission of weakness, and will respond to an Internet snuff film by saying, "Well, that's not nearly as bad as that chainsaw one. You mean you guys have never heard of it?"
Shock hipsters are the worst hipsters.