not sure why....? (spoilers)
...he thought he was trapped in the concert to begin with.
They didn't know what he looked like. The profiler was guessing and the cops kept grabbing different types of men.
The closest they got to him was a generic hand tattoo.
He coulda safely left at any time with just being screened like every other man.
COPS: "are you the butcher?"
MAN: "no"
COPS: "OK you're free to go"
His wife phoned the cops and told them about the house and ticket, but didn't describe him.