UltimateUnknown on 20 February 2013
Have you read the manga? The war isn't the only arc that the manga is covering. There are many other arcs like Sasuke VS Kabuto, Madara VS Hashirama (what is going on now), 4 hokages rejoining the war and the war itself ending. After that there will be another arc that will deal with Naruto VS Sasuke for the ending. So they can easily make another game no problem.
But I think the real answer is that there is demand, and so they are just doing business.
