Ignorance as an excuse

Once again, I found a horse on someone's property, last Saturday, that was at least 300 pounds underweight. The guy, who shall remain nameless, used ignorance as an excuse. Animal control took the horse to vet where she said she's never seen a horse this bad. As of today, the horse is better, but not good at all. So, can someone please tell me the reasoning behind all of this? Is there? Why is it ok to take an animal and abuse and neglect it to the point of death? Where is their voice in all of this? Oh that's right, they don't get one... Where is the law in all of this? Why does society let this continue? If we do nothing, then who takes responsibility? Or has it come to the simple and inexcusable reasoning that we just don't care?