how could he do that the poor dog must have hurt really bad....

If a vet had seen the poor dog, and the man explained his circumstances, i'm sure the vets would have helped him out.
I know my vet will set up a monthly payment scheme for those who can't afford to pay all at once.

Here is a link to the same story, on a new site, with a bit more info: http://news.bbc.co.uk/1/hi/wales/4230306.stm