Because not all of us are ninja fans. I personally like the Shaolin masters more. And while we're at glorifying paid killers, why not go all the way and strive to be like the original Assasins (https://en.wikipedia.org/wiki/Assassins)? Granted, they were Muslim Shia killers that had a bad habit of also killing Crusaders (i.e. Christians), so that might not play out so well on a professional programmer's CV.