Its not really an Anti Gaijin sentiment. Its a bussinesss model. Yes broadening their scope would bring in more dosh, but at the same time it would cost a lot of problems
Keep in mind, the they are not doing only "small" localization to another country, but global in general. The sheer magnitude of such step would require massive preparations and investment, shoudl they wish to strike out on their own.
It would be much better for them to take over (legally of course) a company like lets say NUTAKU, and replacing all of their policies and personel with their own to properly reflect the customer support and care they have shown on their own platform (DMM) there as well