There may be pleasure in watching destruction and harm in a movie, but you always remain a powerless observer, a bystander. You don't actively chose the course of action that leads to the violence or destruction as part of the process of enjoying the game. That's the difference between movies and games of similar graphic violence - a game lets you choose to act out the level of violence you enjoy. As the higher functions of the brain are used to decide these processive actions on a more consistent basis, especially before a brain is fully developed at the age of 25, it makes it more habit forming... something that wasn't a problem when graphics used to be so unrealistic that a more developed brain is able to dismiss it easily as fantasy.
We seem to be getting to the point where virtual reality is looking more like reality... which begs the question - how is watching realistic violence on a game and enjoying it, any different to watching real violence and enjoying it? If you have a game that gets you excited about sniper killing an image that now looks like a real human, how is that different to a serial killer getting excited about actually killing a real human?
And at the accelerated rate of realism in games, how far off are we from a gaming format similar to the movie The Matrix, which would have players enter a realistic world to do their killing and destruction (for pleasure), without anything obvious about it being fake? With 3D gaming being the next big thing, is life-like virtual-reality gaming really that far off or far fetched? Does a line need to be drawn somewhere before we get that far, to restrict 'life-like' graphics to non-violent games?
I think perhaps that the latter is what is happening here, with a point of realism approaching (and in some instances, reached), government agencies are stepping in to suggest setting up the boundaries society needs on things it wants (like with drugs, cigarettes, alcohol, etc). As a gaming culture, we may just be too addicted to a finding and playing a 'bigger high' - the next, more intense game that outdoes the last one at stimulating our senses.
For example, playing out the latest Call of Duty, I was put off on a couple of things, most particularly the torture chapter of the game. Why have this as something the player has to do for fun, instead of just being played out as a scene between chapters (or not having it at all)? It wasn't necessary for the plot of the game. Who gets pleasure (the point of a game) from sticking glass into a person's mouth and then punching them in the jaw to make their mouth bleed? What sort of person would choose without hesitation to do that, or why force a player to do that to proceed to the next chapter?
Games are meant to stimulate the pleasure centre of the brain, so why is torturing someone in such a cruel fashion considered 'fun'? I don't mind shooting-type games for improving reflexes, and maybe even roleplaying certain eras of history (like in CoD), but do people really enjoy torturing or mutilating others for them to want it in increasingly life-like games that are supposed to be 'fun'?
I know I have high standards when it comes to things kids (with developing brains) can be exposed to, but why are people enjoying games that allows them to choose to do these increasingly realistic violent things for 'fun'?
Maybe if we didn't have such a violent nature to our species, we wouldn't have a high demand for increasingly violent games, and therefore wouldn't have games so violent that they are refused classification.
(I blame Dinobot and Cheetor for educating our ancestors on how to be violent...)