I KIND OF get it, but it's not like other industries are any better.
Music has it's 'cop killer' or 'in the name of the king'
Movies have its 'saw' and 'the expendables'
Books have its 'american psycho' and 'twilight'
Comics has its 'punisher' and 'the walking dead'
Tv has its...
The list goes on and on and on.
We're predators, we LIKE violence, it's part of our dna.
As I think others have said too, where as Clockwork Orange, say, or Saving Private Ryan is still pretty shocking in its level of violence and portrayal of suffering, and are known because of that, the vast majority of top selling games have a level of violence that casually exceed these 'shocking' limits. It's a bit strange that one can happily blow through a small army in BF or COD or Halo and not think twice; this might be because the violence in these games is dissociated from context and reality, and the only way developers see to make an impact is to make the explosions bigger and the gore messier. This just turns slaughter into a spectacle, and there's a case to be made that desensitising people to mass slaughter could have a lasting effect on people's attitudes to conflicts in real life..
There's a reasonable argument to be made to encourage publishers to drive for more context and weight to the actions you make in shooters. There was a suggestion a while back about encouraging devs to honour the Geneva Convention in war shooters, and things like that could actually make a subtle difference; people's instinctive behaviour can be adjusted by games, and if you learn to, say, accept enemy soldiers' surrender and are rewarded for it by the game mechanics then it could perhaps be a step on the road to making gaming more than a meaning-less pass-time and potentially a more complex commentary on reality.
That tangent aside, one thing that could be done to make death carry more weight in a game is to have less of it. Compare the 6 or so deaths in the film Drive to the slaughter in a Jason Statham or John Woo film; each of the kills in Drive
had weight, to the point of actually stirring feelings in me that I never thought a film could bring up. Each death carried weight and consequences, affected characters and the audience profoundly, and stood out against the rest of the film's backdrop through dramatic contrast and strong pacing.
John Woo crafts some very impressive fight scene choreography, but there's little there bar the excitement. The death of nameless mook #56 matters not to anyone; it's no surprise that the horde of people wearing white boiler suits that endlessly steam in get instantly killed. The heroes don't really break much of a sweat over them, though they might take a dramatic flesh wound if the scene needs more tension. Not even their employers give a shit - analogous to how the majority of video games work.
I'm not going to say that each and every shooter needs more Drive
and less John Woo, but it would make the genre much more interesting to have a few more mature 'mature' games in the mix.