Just so other Americans know, service dogs do *not* need to be wearing gear that says "service animal", nor do they need papers, nor training from any specific entity.
All they need is training to do at least *one* task that serves to aid an individual with their disability. That's it. This training can come from anyone, anywhere, you can even train them yourself, that right is specifically noted by the ADA.
They must be well behaved and 100% under control, and potty trained. If they are at all disruptive to others in either regard, they can be asked to leave, and you must comply, though you can come back without the animal. A fear of dogs or allergy to dogs is not a valid reason for someone to turn you away. Patrons must be accommodated, both those with the dogs, and those with the related issues. You may not be isolated or otherwise treated differently from other patrons.
People working can ask only two questions to confirm that the dog is a service animal:
(1) is the dog a service animal required because of a disability, and
(2) what work or task has the dog been trained to perform.
That's it. If you refuse to answer, you will be asked to leave, and you must comply. These two questions are the only questions that you *must* answer, any others are not allowed: they cannot ask about the person’s disability, require medical documentation, require a special identification card or training documentation for the dog, or ask that the dog demonstrate its ability to perform the work or task.
You will still be charged for any damages caused by the animal.
Hope that clears up the many misunderstandings I see. I have a service dog, and I'm happy to answer any other questions anybody might have about how this whole thing works.
Thanks for reading, here's a sleepy dog tax as a reward for making it this far.