A popular TV show has been recording the mess that hoarders make of their lives and property. Hoarding has shown us the vast collections of junk that the hoarders believe to be so valuable. When we look at our own accumulation of possessions, we may see the same tendencies, reduced to socially acceptable levels.
An identifiable type of hoarder accumulates pets. Some have lots of cats. Some have a pack of dogs. Some have both, dozens of them. Some have lots of horses.
It may be that those who gather large numbers of animals do so because they are looking for approval. The feelings of animals who wag their tails, purr, and nuzzle in their happiness at being fed can be misconstrued as love for their feeder.
It is the closest thing to love that such people have.

You may be correct about the animal hoarders. There is definitely a compulsive disorder at play here – an attempt to fill a void that is never filled. From what little I’ve seen of the TV show, as well as stories I’ve read locally, many of these prople have adult children who love them, but who don’t live with them. Listening to these people who don’t have animals, so much as lots of things – many of which are absolute junk – these things are a desperate attempt to make them feel secure, somehow.
As a confessed pack-rat myself, I have tried to be vigilant and watch for signs that I’m crossing that invisible line between “pack-rat” and “hoarder.” I suppose the difference is, after awhile, I get disgusted at the clutter and I start cleaning and throwing things out.