If you're looking for accurate roleplay, Munchkinism is part-and-parcel because there are real-life Munchkins. There are, indeed, people who play the system, people who hyper-specialize, in real life. So why is it unrealistic to run into a character in a game that is supposed to mimic real interactions among people who has decided to hyper-specialize and take the path of least resistance/highest efficiency to their own personal goal? Such people, in real life, are often rather shallow and one-dimensional individuals as well so the fact that such characters are focused and one-dimensional is no big surprise. So long as they aren't breaking any actual rules, but simply pushing valid rules to their limits, they are playing the exact same game as the rest of us; just differently. In fact, it's just as valid an argument that if you play a sub-par character, highly de-optimized for the sake of "roleplay", one might criticize you for poor roleplay in that such a character wouldn't reasonably go off on some big physically and mentally demanding adventure. That's the other end of the spectrum; the player who is so focused on a particular character roleplay that they forget the mechanical aspect of the game. It isn't a matter of mechanics or roleplay. They are not separate; they are both integral parts of the same game. They are reciprocal; mechanics reinforce roleplay and roleplay, in turn, reinforces mechanics. Keep both in mind and remember that there are extremes on both ends of any spectrum.
