Charlemagne
Black Belt
Because you are familiar only with a specific model of training. That model of training, while effective for one type of martial art, isn't necessarily effective for other types of martial arts. It all boils down to the focus, goal and teaching methodology.
No, that isn't it. I've trained other supposed martial arts that never sparred, to include some of the ones mentioned above. And yes, sparring is effective for any kind of martial art. Pretending that sparring is not necessary in order to be able to pull off your techniques against someone who is trying to resist that is delusional.