I don't know either if this story is true or not- I find it unlikely that the dogs never fought and I have real issues with him releasing pregnant cats and kittens.
But the basic reality is true- I worked at a kill shelter for several years as a volunteer- we would get in some really pathetic dogs. I remember this one who almost had an embedded collar from being tied up her whole life, feces matted to her long fur... I brushed her out and she loved the attention, was such a sweatheart. She died the next day from seizures but if she hadn't probably would have had to be put down anyway. Too sick, too old, too many animals. At least she got that one hour with me. At least she didn't die without ever having someone pet her. I didn't want to go a lot of times, especially when the intake was too much and the dogs only had a week or less, but if I didn't go walk them, no one would. Sometimes I would think "If I just don't go this week, I'll never even know what dogs died because I never would have met them" and then I'd feel like a horrible person. It's not the dogs fault and not going only hurts them. For a while I didn't ask when an animal went missing, but eventually I got up the courage- it was good to hear that a favorite had been adopted. It sucked when all I got in reply was a sympathetic look. Nobody enjoys working in kill shelters- it really sucks and eats you up inside.
There's a great (really sad and graphic) video:
Born to Die that tells the hard truth. I just watched it again and I'm bawling- both from the posted story and the video. You want to adopt them all, but you can't. It's just not possible.