Do Androids Dream of Electric Sheep?

Ever since I started reading Do Androids Dream of Electric Sheep? by Philip K. Dick, I find the fact that the characters are obsessed with animals to be kind of odd.  During the first chapter wen Rick Deckard was thinking about his electric sheep and going up on the roof where the animals are kept I thought that this would just be a small part of the story.  After I went on to read the next 3 chapters I found out that I was wrong.  Rick has this major obsession with animals and all he thinks about is getting a real animal. And it's not just Rick that seems to be fond of them, pretty much the entire human population left on Earth has an obsession with animals.  I find it weird that they have a monthly catalog just dealing with animal sales.  This may not seem strange to some of you but the prices for these animals are ridiculous.  People spend thousands and thousands of dollars just to get the best, or rarest pet on the market.  Rick's entire happiness practically depends on him getting a new animal.  The fact that he is practically depressed just because he has an electrical sheep instead of a real one is ridiculous if you ask me. And when Rick goes to the Rosen building and see's the animals, especially the owl, he acts like a two year old at a zoo.  I understand that it a person would be awe-struck if they saw an animal that they thought was extinct but I just find this whole obsession with animals both weird and interesting. Although i have a basic knowledge of why they are obsessed with animals, I hope to further understand it as i read on.