Is "Ghost Hunters" a real reality show?

I only watch Ghost Hunters when I encounter it channel-surfing and I’ve never seen a complete episode. And I’m a hard skeptic about ghosts and psychic phenomena. But I always assumed it was a “reality show” as it’s most often described. That is, I assumed that maybe they’re making more than is justified out of the “readings” of their “instruments,” but that they are sincere ghost hunters going to places genuinely rumored to be haunted. But recently I saw a teaser on the Sci-Fi Channel about the upcoming episode – hunting for ghosts in “Shawshank Prison.” Now, I’m a Stephen King fan, and I’m fairly certain there is no real Shawshank Prison in Maine or anywhere else. Was this intended as a tipoff that whole show is John-Edward-grade pure bullshit?

They’re referring to Mansfield Reformatory, where Shawshank was filmed.

Oh.