What I did:
I had two different play areas and only one had a region around it. Outside the region, I had actor A create another actor B at a random location nearby. When I moved the view to the A actor, it created the other B actor fine. When I dragged the view until the original A actor was out of the view, suddenly a bunch of B actors were continuously created until I dragged the view back over A. It seems as if A's create actor script was being run every frame when A was not in view. Removing the region made this behavior stop.