I also know a few people work as volunteers in the local animal shelter. Most of the animals there eventually find a permanent home. Not all animals there are being abandoned though. Some were just found wondering around on the streets. They might be just lost their way home, and since nobody know who they belong to, they are sent to the shelter.
The cat and the dog are in love. They wrestle and play with each other all day long. I mean, I've got the dog on the dining room table (and he's 70 pounds) because the cat was up there teasing him. They are good buds and for that I'm grateful.
And the cat gets along with all of my foster dogs. He especially love the puppies. To him, they're like other cat sized things to play with. He'll pounce on them and they'll chase him. Good socialization for the puppies. We've only had one foster dog that didn't like the cat: a border collie with a crazy crazy herding instinct. She never left my poor cat alone.