People often claim that the difference between movies and games is that in games you yourself are the one perpetrating the violence, whereas in movies you are passive.
But that’s exactly the reason, why violence in games is often negligible: Players are to busy playing the game and taking care of so many things simultaniously that one doesn’t have the time to really focus on even the most violent things.
Plus even the best graphics are still miles away from being even remotely as realistic as movies with their elaborate special-effects. You may observe the corpses after a fight, but even when they do have bullet wounds or something similar, textures and details get blurrier and mushier the closer you look. So if at all, watching even relatively harmless movies like, say, Pirates of the Carribean is more „damaging“ than playing a plain shooter, because as a passive viewer you have more time to focus on every bloody detail.
Also people are exaggerating the effects of violence through gore in my opinion, whereas the „psychological-violence“ (can’t think of another term) has the far greater effect. The Last of Us (TloU) for example has considerably less gore and dismemberment than Bulletstorm, a game which is wholly designed for killing the enemies in the most brutal and creative way possible. Yet I would argue, especially with regard to the prologue and the end of the “Winter”-Chapter that TloU is emotionally far more brutal and traumatizing than Bulletstorm.
Besides, it does not matter what kind of violence is displayed in games. Since there are no real persons being hurt, nobody has the right to forbid anything.
However, as the critics of video games often prefer to just attack the most commonly known shooters (especially even the harmless ones like Counterstrike), they demonstrate that they have not concerned themselves with the topic of violence or games in the slightest and are not willing to do so. One could almost ignore such ignoramuses if they did not always try to dictate what one should consume.
When Dead Space 2 was evaluated by the USK (the german ESRB) at the time prior to its release, they checked it five (!) times before it finally received the “Keine Jugendfreigabe”-seal (the equivalent to “M” in the ESRB-rating). The Christian Social Union (CSU) did not like that at all. So they pulled out some old paragraph nobody has ever heard of to force the USK to check the game a sixth (!!) time – a game where you should know at first glance: “Yep, Mature” – and so tried to prevent the release. Fortunately, the USK was reasonable and granted a release. God it was satisfying to read about these christian-wannabe-fascists “outrage”…