Traditional Gaming is a dictatorship.
It could be a benevolent dictatorship with a GM sitting at the head of the table, carefully crafting a story by picking and choosing from the actions of the players who follow along blindly, rolling dice every now and again, but basically enjoying the story ride.
It could be a malevolent dictatorship where the GM still sits at the head of the table, but now exists in a more antagonistic role, hammering down any players who choose to step outside the bounds they have defined for their story.
I've played under both styles of GM. I'm sure that anyone who has played in more a couple of games (and who has had the opportunity to play under a couple of GMs) will instantly be able to think of games where these two cases have been applicable.
A lot of players like the idea that they can put a character into a world and have the GM work this avatar into a storyline. Many of these players quickly get bored.
When I created The Eighth Sea, I specifically didn't call the lead player the "GM" or anything similar. Pirates were one of the first social groups on the planet to institute the notion of democracy. If they didn't like their captain, a vote wold be called and a new captain would take command of the vessel.
My aim here was to create a system in which the storytelling role was a transient one. If the players didn't like the stories being told, they could simply vote out the current storyteller, and another of them would have to step up to the role.
This has a two-fold effect.
Firstly, the GM/Storyteller/Narrator/Captain has to keep on their game. They have to be consistently producing enjoyable storylines where everyone feels satisfied with the events, otherwise they could be put forward to a vote and could be ousted from their role.
Secondly, it stops players complaining about the GM/Storyteller/Narrator/Captain. Once they start complaining, then people ask if they are willing to step up and do a better job themselves. It seems to be human nature to complain, and then to back down when a person is called out on their beliefs. The complainers tend to shut up pretty quickly when they realise their own abilities might be critiqued in the next session.
I haven't managed to play a long term campaign under this style of "GM Democracy", so I'm not sure what effects it might have on a campaign in the long run, but I could easily see that if a player steps up to the role and makes the campaign take a sharp turn to the left, then the players will probably mutiny again at the end of the game (unless of course everyone felt the sharp twist in the storyline was necessary to inject some freshness into the tale).
The Eighth Sea actually takes the democracy aspect a step further, with all of the players getting the opportunity to add their own twists into the tale during the course of the crew's adventures, but that's a mechanism of it's own and will be expanded at a later time.