*hasn't read the whole thread*
Now I can see both sides of this. As a dog lover and having frequented dog forums that have disabled members, let me say that service dogs exist for more than just blind people. I know someone in real life who has MS, and he recently bought himself a dog to be his service dog. He's in the process of training it. He has a legitimate need that needs to be filled. Another example is a seizure alert dog, a dog that assists deaf people, or a dog that detects when a diabetic has low blood sugar. Service dogs are not limited to these functions, though. Disabilities are not always visible.
Neither are all service dogs registered with an organization. Some, like the man I mentioned above, opt to train the dogs for themselves.
Also, therapy dogs are completely different from service dogs. Service dogs are trained to help someone deal with a disability. Therapy dogs visit people in a hospital or nursing home to cheer them up.
There are also emotional support dogs, but none of the dog people I've talked to consider them service dogs at all.
