They are all legitmate playstyles. And none of us have the right to say they are not. Some we may not like but it is not our choice or right to say how another player should or has to play the game when on our team. They have just as many rights to play the game in what ever way makes them happy as anyone else. We may get to not like it; but we do not get to try and say it is unfair or bad or wrong or should not be allowed. We did not make the game, so we do not get to make the rules about how the game is played by anyone.
Campers: Never had any serious issues with them.
Snipers: Im a fairly good sniper with a ballista. I usually hold down the bomb in the garage on nuketown.
Quickscopers: They annoy me sometimes like when im about to shoot my ksg at them and (gunshot) Im dead and im not a good quickscoper and the times i get one its pure luck.