It's especially bad in C&D as a defender though. I used to use it with a shotgun and could walk right up to the attackers since they hesitate and think you're on their team at first. I managed to kill Snake, and 3 other people before they really caught on.
I don't have a problem killing them for the most part and I hope people will just get used to it and notice the lack of nametags, minimap location, etc. and kill the person, but I understand why people wouldn't want it in the game. Otherwise, C&D is the best mode in the game by far.
I really just need to make a loadout to deal with the walkers. I wish grenade throwing wasn't such a pain for a MP game (not bad in a slow SP game) since a good ol' molotov kill is always fun. My enforcer class does alright against them, but my main infiltrator character has to pray the walker player doesn't see me so I can shoot him in the back.
Also, how do heroes work? My friend got to play as Ocelot his first game and I've seen Snake plenty of times, but I've never once seen him as an option in my loadout screen. Is it just random to one player each game?