Modern warfare

My two great-nephews play a video game which mimics a war zone where soldiers battle and kill one another, several times in the course of a game. I have never seen one of these before and was frankly quite shocked at the violence. So I had a discussion with the boys and their parents and they explained that they monitor the game time, and the dad plays with them, and they talk about the cartoonish nature of video games. Still, it was a bit shocking to see for the first time. Anyone else out there have a similar reaction to modern video games?