I've been told a few times that one cannot be against war (or the army) when he plays war games. That's not true. War games only simulate the funny and good parts of war. Yes there are some good things in war and conflict in general.
First of all they give you controlled violence. Most people (especially males) are inherently violent. Society makes you inhibit these instincts and empathy makes you realize and in some cases feel the pain you cause if you become uncontrollably violent. But because no instincts can be truly suppressed, without a cost, society provided, throughout history, ways to let the steam off: controlled wrestling, soccer (Laaaame! you call that violence?), and lately: war games.
Secondly, war is about cooperation. You obviously can't accomplish anything if people don't cooperate. Until now, it looks like the most efficient way to cooperate under stress, is centralized control via a pyramid scheme. People like cooperation whether in war or not, and war games provide that. But the best part about cooperation in war games compared to cooperation in real war is that in the game YOU get to choose your leaders, IF you want any at all, while in war they are forced upon you. I would hate having to follow orders from some drunk useless guy just because he happened to be over me in the hierarchy. On the contrary, I loved following, almost blindly, the orders of some amazingly organized squad leader in BF2142. If you get to choose the people that I will cooperate with, cooperation will always be fun, while in the army you just have no choice.
Accusing someone that liking war games is the same as liking war itself is no different from accusing someone of liking death because he laughs with black jokes, or being racist because he laughs with racist jokes. Or accusing an actor of being Nazi because he really wanted to play Adolph Hitler. A joke is joke, an act is an act, and a game is game. I (and most people) would OBVIOUSLY stop liking war games the minute death in them was made permanent or killings in them resulted in children left without a parent. Sane and educated gamers realize that death in real life is permanent and not fun. If some don't, well... as I said: "sane and educated gamers". You'd better start looking for some other problem in your society that's causing those minds to fail to realize why real war is bad. Let's say patriotism (especially if it's taught to children) or anything that makes people value someone else's life less than their own based on imposed differences like ethnicity or race.