Why do some people so love to dig up and pass around "dirt" on others?

Most people love to gossip.

cause the people that do it are being nnean

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. 

I would guess that at least 80% of the time it's make up and pass around.....