Sadly, the idea that TMA are useless is an attitude that many of us have had to deal with. Some face such criticism with a shrug, others with a militant defense of their years spent training.
Unfortunately, I face this attitude on a daily basis teaching karate to deployed troops here in Iraq, especially since the advent of the "Modern Army Combatives" system which is very BJJ/MMA based. "I don't need that...I do combatives!" is a common response. I usually smile and let them go on their merry way, since there is little that I can tell them that they are going to listen to. I do, usually, invite them to class anyway for them to see if they might like it. Those who do show up usually tell me the next day or the day after next about how their legs are so sore from that horse stance thing....
I make no bones about telling perspective students that if they believe that they will successfully defend against an attacker swinging a pipe at their head with a rising block from front stance and finish them off with a reverse punch, that they will probably be dead and minus their wallet. I do, however, point out that the same principles taught in Front stance, high block, reverse punch and so on translate directly to a practical method of self defense. The only difference is in how we get there.
A particular individual that I worked with, any time the topic of unarmed combat training comes up, would say "Thats why I got a gun!" or some derivative of the same sentiment. This, too, is a common response shared by many nay-sayers.
The difference between many TMArtists and many MMArtists is this...most TMAers will be willing to study MMA material, but many MAAers won't study TMAs.
My two bits.