When they say "Go play a real game like cod." just laugh in their face. And then walk away, laughing.
Also, no one says that. I don't know why the internet has such a hate boner for CoD, to the point where they make up these wierd "gaming jock strawmen" to villanize, like this is some sort of take on an 80's teen comedy. Unless this is how people talk and act in high school nowadays or something, it all seems kind of made up.
Congrats, you do not like CoD despite it being popular by the mainstream. Completely understandable. But to villanize those who do like it make it sound less like you don't like certain aspects of the game, and more like you are hating on it because you want to "fit in".
I do come off as that, don't I? Maybe I should explain my take. I would never villanize (is that word? I'm not questioning your intelligence or anything, but I never heard it used before.) anyone for liking things different than me. As you said, no one says "Go play a real game like Cod". But, in the hypothetical scenario that someone does, this is just my reaction. But, yes, I did follow a social meme that "It is cool to hate on Cod." And I am sorry.
Philosophy: Needs more Ice type, and Dragons are the devil.