This has been an interesting thread, and I'm glad I started it.
In the U.S. there's already quite a few businesses that will allow you to bring well behaved dog's in, regardless if they're service dogs or not. I've taken Charlotte and Ma'ii into dog friendly cafes, bookstores, and even a ferry in the past without issues. In an ideal world, all buisnesses would allow this, but it's completely understandable and reasonable why they don't, and I think it should be respected. The service dog program was created to help people who can't get around normally on their own, and need assistance, not because they want special privileges and to take their dogs places others can't. Taking advantage of it is selfish and disrespectful.
With all that being said, I make it sound like I care a lot more then I really do. I found out about the service dog scam from a group of hitch hiking friends of mine who own dogs. They have been doing the fake service dog thing for years now, as a way to travel easier around the country. This way they can take their dogs on greyhound busses, into stores, hotels that don't allow dogs, etc. Rude and selfish, but... whatever. If they get caught, I can't say I'd feel much sympathy, but I'm not going to out them.