Computer games are what they are - computer games . Games are meant for fun and entertainment, not reenactment. That's common knowledge. Hunting is violent. Driving a car can be lethal.
Football encourages beating the crap out of other players.
If an activity is deemed violent, it's the moral responsibility of the participant to know and understand the difference from their activity and real life. For example, if someone hunted, they should know and understand you hunt animals and not people. All of this boils down to common sense. That's how simple is really is. Of course, there's plot twists to it, interactions of subplots and the occasional surprise, but that's what it all gets down to.