I believe you. I'm sure there are plenty of people who can play with a gamepad about as well as a mouse and keyboard, but what I'm saying is what about the rest of the players in servers? Most of them won't be playing like that person, which would make it a very different experience.
Of course, there's always the option for allowing KB/M controls, but I'm ALWAYS against that in console games despite being a huge PC gamer that prefers KB/M controls. I feel like an ass using that setup on the PS3 version of CS:GO and I also don't like to have to think about other players using a KB/M setup when I'm using a gamepad.
Well thats why it would be only console vs console and pc vs pc to keep the playing field even, console will lose out on game size being like 6v6 or 8v8 at best.