Dogs aren't wild animals.
Dog owners pay is my guess as they are required to maintain control of the animal.
I get this but why is it different because the dog has an owner? They are still animals with a mind of their own. It wasn't like the owners had intentionally let it run free. What if it was a stray dog?
The only difference is the owners may potentially have insurance that will cover the damages. Otherwise it's the drivers comprehensive insurance that will pay if he has it.
It's different because the dog has an owner who is responsible for keeping control of the dog. An adult pedestrian is also liable if they are crossing the street illegally, run into traffic, etc. and get hit. They are responsible for the damage caused to the vehicle. If it's a minor, there are statutory considerations that may prevent the parents from being held liable in some states, in some scenarios. Generally speaking, if a minor runs into traffic, rides their bike into traffic, etc., the parents will be held liable for damage done to the car if the minor is struck.
The reaction of the parents, and of the crowd of onlookers who witnessed this, indicated that a lot of people though that the poor guy driving the car should've just sucked it up and eaten the cost, and that he was an a-hole for not doing so.
