MMA as a whole seems to me to attract a crowd of people who prefer martial arts for, as I stated earlier, "kicking ass" While most aikidoka I have met aren't in it for learning how to fight. Sorry to have offended earlier. Thanks.
Some people in MMA are on a more esoteric level than that. They are genuine artists who want only to hone a personal martial art that is the most effective art for them. They're crafting their own suit that fits them to a "t." In "pure" arts, the student has to fit himself to the art; in MMA, he custom-tailors his own unique art. The main characteristics are that it can't be rigid - it must allow the person to adapt to the environment and circumstance, and, function is key. Without efficacy, there is no legitimacy.
It's not about wanting to "kick ass" and being a tough guy. It's about wanting to be genuinely effective. Big difference.