Some people play this game because they enjoy playing the game, and all the aspects that it entails. Sometimes, that means taking on a challenge that may not be the most rewarding experience in terms of success in deathfulness, or merely survival. It has other ways of being suitably rewarding, but I'm pretty sure, having played against you, that you're very well aware of that.

Some play it so they can talk shit to whomever they think will listen, also known as the power gamer (this also includes the smug bastards who power game and never speak up, but they don't bother me as much, since they tend to cheat less or not at all, anyway).

Some enjoy having large groups of people supporting their characters, then acting like the group accomplishment, constructed outside the frame of the game and perpetrated within it, is some incredible accomplishment on their part. Somehow, this approach validates their opinions, of the game and of themselves as skilled and/or intelligent beings.

Sadly, this approach does not encourage the undertaking of challenges that do not support the power gamer requirements. No, those requirements, as you argue, are the cookie-cutter, quick to rank, easy to maintain, and group killing skill sets characters.

The irony, of course, is that when these players grow bored with their endeavors, as inevitably happens when you cheat to rise to the top, they'll bitch that the game no longer entertains them, and leave. Whereas the gamer who has learned to enjoy the game for more than the technicalities of the killing aspect will continue to walk away from the game with a sense of accomplishment inherent to putting forth your own best effort, and knowing that what you've done was yours, and no one else's.