The noise??? Be real, this was planned well in advance. He did not just get pissed about concert noise one night and open fire. He chose to massacre concertgoers for some reason(s) as yet undetermined, and he had to spend significant time preparing such an attack.
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I’m pretty sure that wasn’t the first outdoor concert in Vegas.
I wish you would make your point clearly.
Are you trying to say that he hated the noise of some previous concert, so he started planning to shoot up a crowd at some different, future concert??? That sounds more bizarre than anything we have heard, although I admit that there does not seem to be any good explanation so far.