This. If I just ruined someones day with a ticket, I'd be nervous hanging around by myself in the dark on the side of the highway "helping"; perfect setup for revenge, etc.
Though even if you were just helping, wouldn't you always make passengers ride in the back, even if they aren't in custody?
MOST Cruisers do not have transport cages in them.... in fact my department transports prisoners in the front seat.
Since he was not under arrest the passenger was given an officer safety pat down for weapons and the guys demeanor was very calm.... until he flipped out.