Can see how it would be usefull, ie if they release a game every few months that you don't have to pay for if you are subscribed.
Then again, from developers point of view, the upfront payment method is not always the best. If we take Rovio for example with it's Angry Birds game, it has now made as much money from iOS sales as it has from Android, despite giving it away for free for the latter, and expects to overtake it soon as with the ads based model, the revenue continues to tick over.
Either way, the reason why Apple pulled this app is simply because it won't be getting a porting of the monthly sub, simple as that.