well 3 years of ju jit su doesnt make you an MMA fighter, u only studied one art form, so technically if you wore MMA gear urself, ud be a poser like the rest, youd need to study other art forms to be considered a MIXED martial artist...
but yes it is annoying, i hate it too, but its no different then wearing underarmour, nike, adidas, puma, a teams sports jersey, your favorite teams fitted basecap... its just another brand of sports that people are into now, the fad will die down soon...
but you are right, 99% of the people that wear that most likely couldn't crush a grape in a fruit fight
i am a second degree black belt in kempo karate, have studied muay thai for 3 years, and boxed for 14, the thing i hate is when people find out that i am an amateur fighter, they ask "oh do you do UFC?" I say no, i do MMA. UFC is a company not a sport, i dont go up to someone wearing a nike basketball shirt and say "oh hey, do you play nike?"