This man did not react like this because he thought the police wouldn't do anything. He didn't react like this because he wanted to get his bike back - he rammed it five times and couldn't care less if he wrote it off. He did it for one reason - to give the thief a good hiding, to take out his anger on him.
He didn't give a moment's thought for anyone else on the road.
I've been burgled and know how devastating it is to be the victim of property crime. I've also been in the most horrific car crash where several people died because of an idiot racing his biker friends on a very fast motorbike. That accident changed my life forever. So yes, I do know what it is like to be the victim of crime.
Had this man just punched the wall in frustration, screamed a few bad words and cursed the thief, he would not be in prison, his insurance company would have stumped up for his stolen bike and (probably) that lad would not have died.
He saw red and reacted to his temper.