There are SOMETIMES good reasons to give up a pet. Most of the time people have horrible excuses and when you get down to it, they just don't want the dog anymore. They make excuses or they blame the dog. In reality, it's there fault for not wanting to take the time to train it and are just flat out lazy!
SO as long as we have lazy ignorant people, well have this problem. I don't see an end to it anytime soon. :(