Welcome to Jemsite!Why are some models not available in some regions? . . . .
You have identified a common complaint among Ibanez fans all over the world. Europeans are mad they can't get guitars available in America. Americans are mad they can't get guitars available in Japan. (Everybody's mad they can't get guitars from the Los Angeles Custom Shop, but I digress.)
I don't know why and I've never heard a good reason. The closest I've come to hearing a good reason is that artificially restricting demand in certain markets generates interest, buzz, talk, and eventually higher demand. Never mind that it annoys and frustrates many people who can't get what they want.
I have never been employed as a marketer (and nothing but), but marketing has been a part or a function of my jobs. I just don't get it.
I was in Paris and passed by a music store window where I saw an Ibanez guitar in a finish that wasn't available in the States. It was gorgeous. You can quote me spreadsheets and surveys and theory all you want, but the bottom line is that ANY guitarist-- be he a Frenchman, an American, a Brazilian, whomever-- would have loved that finish.