#3 It creates more scope for a future Fiend vs Demon match
With both Bray Wyatt and Finn Balor trading SummerSlam wins as their unbeatable alter-egos, it would only make sense for the both of them to have a spooky blowoff at some point in the future. And that is money. The two could have said match at WrestleMania 36 or, possibly, next year's SummerSlam. Honestly, the Demon character is not exactly working as well as it used to and it could do with some changes.
This could have been the time for the Demon to be defeated on the main roster, but it is understandable why WWE would not want to do that right now. However, they really should consider having a do-over for Balor's face painted alter-ego. His use of the character over the past year has not been the most thrilling, using it against Bobby Lashley and Andrade, while he faced Brock Lesnar without the paint. That being said, Bray Wyatt's Fiend should come out dominant over anybody, including normal Balor right now, as well as Demon Balor in the future.