As a trainer of service dogs I think it's completely selfish to simply want to kink the system. These dogs are worth 50k by the time their intensive training is completed, and they aren't placed until they are about 2-3 years old. There is so much time, care and money that is involved in this process. That being said, I don't see a reason why any dog can't perform a service to a human. After all, they are ALL performing services, right? Giving us love is a huge service! Unfortunately, dogs just don't fit into our society the way they do in Europe, which saddens me. It's amusing how dogs are so accepted, yet they're almost a burden when they infiltrate the public world in restaurants and stores!!
Bottom line is that having a service dog is more than just needing the dog for companionship. This could definitely be a disability, but it isn't right to just want to break into the system (this could all be fixed by allowing dogs, eh??). The dogs we train are for blind, deaf and physically impaired. The government defines a disability as something that inhibits major life activities. However, courts haven't given a true definition to "major life activity", so you could argue many different ways...sorry for going OT. I just thought you might like to hear it from someone who trains, because this is a huge thing...not something that happens overnight. It is painstakingly difficult!