Passes the time? They have nothing better to do? It makes them feel better about themselves to run others down? All of the above? But being generous sometimes it's borne of a genuine interest in people? I love to know about what's going on in people's lives.. I like to follow their story, to see them develop and overcome difficult times. For me the ONLY thing about my job that I actually like is that I get to make genuine connections with people
I think Adaydreambeliever probably has the best answer.
I doubt that people go to the effort and expense of "digging up dirt" unless there's an important reason behind it: to bring down a rival or enemy in commerce or politics to find out whether a spouse is being faithful to determine a potential employee's fitness to find out whether others have been happy with a tradesman's or professional's work
When it comes to gossip; it often creates a sense of being linked into some kind of community, of belonging and connection between members. In rural communities, such gossip is sometimes the only way to find out whether someone is competent and trustworthy at what they do.
Society loves tragedy and the misery of others. Notice how the news is mostly negative? Notice how in America our society is obsessed with celebrities, athletes and their personal lives? I think at least in part, it takes their minds of their own misery and suffering.
my2cents 