So? Japan is secondary to Disney. Hell, most Disney Animation Studios films tend to have better French, German and British grosses than Japan. Japan would only be primary for Pixar movies, as it is the 2nd largest market for those movies. Dubbing/Subbing simultaneously would prevent stuff such as fansubbing. Isn't that smart? Also, by the time the film is dubbed, people would have already seen the film. The film's hype would have died out long ago. If the Japanese want to prevent illegal fansubbing, they should just allow their films to be dubbed/subbed just after the initial release.
Look into the fears Japan has of reverse importation and the insane prices they try to sell their anime for, fear of American fansubbers is a small issue to them (mostly fansub groups just screw over American fans).
Look into the fears Japan has of reverse importation and the insane prices they try to sell their anime for
To expand on this: Japanese buyers spend, on average, six times the amount of money a North American buyer does on a single season of anime, so a lot of Japanese companies really fear reverse importation from NA to JP because it's much, much cheaper to import than to buy it straight from Japan