I think they were surprised at the photo release and how quick that the US cops were onto them. They started to make one-star decisions...on the spur of the moment. Staying in the local area...I would admit...was not a great idea. They had some place set-up and felt it was safe until the photos were out.
Also, I think it's possible that one of their own was videoing them...I think Usama called them training videos.
Probably working at the 7-11
Did they do the robbery? Not exactly a low key approach.