Wow. Just wow. I feel so bad for the dog. This situation, like you said, could have been avoided.
When my mom's 12 year old dog Lucy (a red nose pit bull terrier) was suffering of persistent skin cancer, hip problems, and had lost 14 pounds for an unknown reason(not worms), we made the hard choice to put her to sleep. For a while pain meds would work, but after a while she required too much meds to stop the pain. So much that she would have begun to get lethargic and stoned. We knew it would be unfair to keep her in a drugged and uncomfortable state just to have her around longer.
You are not alone in seeing the actions of Hurley's owners as unfair and selfish. I feel for you and am sorry for the situation you have been exposed to.
Thanks - Mouse