It doesn't seem to make sense that they would wear masks during the shooting. Eric was out to get those who wronged him, and to show that he was the strongest/the best - it wouldn't be so personal, and they may not have even known it was him had he been wearing a mask, seems counterproductive to me. I'm not sure I'm on board with this theory.
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I had it all and I looked at it and I said 'this is a bigger jail than I just got out of'.