Someone (possibly Ames, not 100% sure) said he read an article in JAMA that contained a study relating to violent encounters outside of MA classes. The study apparently found people who studied MMA were more likely to encounter violence or get into fights outside of class compared to TMA students.

I haven't seen this study, so I can't comment on it. They study did mention that a possible reason for this was that many MMA classes lacked the philosophical framework that accompanies many TMA.

That said, there are many TMA instructors/classes/orgs that lack morality or a "good" philosophy. See the several cases of TMA instructors abusing students in their trust, or the horrible case of a 6th Dan Karate-ka who killed his own children (and apparently physically abused his step-son):

Another example would be (as discussed recently in the TKD forum) the corruption in the WTF.

Bear in mind too, not all philosophies taught in TMA classes are conducive to being a content, law-abiding citizen in the 21st century. I have been in TMA classes where an instructor is telling students about "the way of the warrior" and about "defending your honour". It transpired that this really meant beating up anyone who insulted you or who looked at you cross-eyed!

When it comes down to it, you can be philosophical and find meaning in almost anything. Archery, poetry, music, running, martial arts..... It comes down to the person

As a wise man once said, "It doesn't matter what you are doing, only why you are doing it." This is actually represented well in the original Karate Kid movie. The two sensei (Mr Miyagi and John Kresse, head of the Cobra-Kai) were doing much the same thing physically: punching, kicking, blocking etc... Where they really differed was in the philosophy behind their karate.
"Let your food be your medicine, and your medicine be your food" Hippocrates.