The problem here in Thailand is that they do not treat their dogs as pets the way that they do in the West. They do not sleep in the house, are allowed to roam freely all day and night, and therein lies the problem. You get bitten by such a "free roaming pet", and "Not my dog!", but you hit it with your motor bike, and suddenly it IS their dog, and furthermore it's a Cruft's Best of Breed Champion!
And even if a dog is terminally ill, vets will not put them to sleep as (a) it's against the Buddhist "religion", and (b) they make more money every time they give it an injection, more pills, more taking to and from the Animal Clinic - in short, more MONEY!!!