I bet there is some threshold at which the movie does worse in the long term with limited release. They can still do a full release in the future and part of the profit is purely from buzz and social momentum, followed up by video sales etc... So they can probably just wait until it's worthehile for a full release. The newest Hobbit movie was ready for summer release but pushed to avoid competition with other hits. If they can wait 6 months, I'm sure Sony can wait here with minimal losses.