I have to respectfully disagree with you. I train at a gym that offers Muay Thai, BJJ, MMA as well as traditional MA's. The whole "prize fighter" mentality of the large ego and the assumption that it is all "about money and entertainment" is rather dismissive of men (and women) who train very diligently, sincerely and are extremely dedicated.
The fact is, most people who train MMA will never fight in a large event and even if they do it is definitely not about the money because even at the higher levels the payouts are small unless you are one of the few Randy Coutures or Chuck Liddells.
Of course there are fighters with large egos. I think anytime you have any high level athlete who has dedicated their life to a sport and is confident in their ability they will be accused of having "ego". The guys that I have trained with that have fought in the UFC, IFL, and KOTC are the most helpful, accomodating guys who are sincerely interested in making the sport grow. They do that through training others, seminars and making sure even the newest noob that walks through the door is given the opportunity to train without being harmed and encouraged even though they may never want to be a UFC fighter.
I think people who see MMA as harming the public perception of Martial Arts in general are people who don't really know what MMA is or have no experience with the training and methodology behind it. They are all too eager to condemn is as thuggery and "street-fighting" without taking into account the countless hours these competitors put into studying all ranges of combat.