They'll have livescanned him, so if he's ever met the dibble before they'll know who he is. Problems, even once they've established identity, his behaviour gives reasonable grounds to believe that if he won't cooperate by giving his name he certainly won't cooperate by turning up in court, so he's talked himself into being remanded overnight. The courts quite happily let murderers and rapists out on bail to offend again while awaiting a full trial, so its not surprising they then let this chap walk.
But what a waste of police time and public money, all because he didn't have the stones to take a telling off from a PCSO.