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.
			
		