I don't see how it's
that unlike Final Fantasy. I could see how the movie could be turned into a game. It's fictional, there's a hero, there's a group of people completing tasks (collecting those thingies she needs) and killing monsters, and they save the world in the end. The only things not really Final Fantasy-like are the fact that it somewhat takes place in a real location, the lack of chocobos and Cid

, and there wasn't exactly a final boss (though there was a final dungeon), and I guess there wasn't exactly a main villain they had to fight.
There's a lot more story and less fighting in the movie vs a FF game, but it is a movie and not a game.
And I don't think they would've made any money had they not called it Final Fantasy.