In some sense all TV is reality TV. Those really are real people saying their lines or doing stuff. What you see happening is actually happening.

What you make of it however, is something else, and it's true to say that all TV is, for the viewer, completely unreal. It's a little like reading someone else's thoughts. You have no idea how crazy they might be.

I would go even further, having just watched an episode of "Intervention". Reality TV is paradoxically less real than fiction, because the experience of having one's life in all its sordid detail broadcast to millions of people is highly unusual. In fact, the impression that this is happening would be an intolerable paranoid delusion.

So how is it "reality" TV again?