Take a look at the general type of people who "have to" give up cats and dogs just around the 1-year mark. They are fat and poor. They impulsively spend their money on a kitten or puppy, then a month later realize that the expense of keeping the animal cuts into their beetus, and that they have to clean up after the animal. The animal immediately gets less cute, so they ignore it for 8 months and then claim they don't have enough money/time to take care of it. This isn't every single person who has to give up a pet, of course...but it seems to be a lot of them.