#1 To extend Roman Reigns' anti-authority feud
In case you missed it, Elias was introduced to Smackdown Live by Vince McMahon as the biggest acquisition in Smackdown Live history. In the coming weeks, Elias sided up with Shane McMahon, who has been making some totalitarian decisions on both RAW and SmackDown.
WWE might be looking forward to extending Reigns' feud against Elias, and in turn Shane McMahon, at least until SummerSlam. Reigns' victory yesterday was not clean by any means. The Big Dog gave a Superman Punch to Elias before the match even began, rendering the whole match tainted.
Elias may use this excuse to earn another match against the Big Dog at Super Showdown or even at WWE's newest PPV, Stomping Grounds. That match would result in Reigns' full-fledged attack on the authority that may culminate at SummerSlam.