My friend just got her dog trained and certified to be a service animal. It was a real program and her dog is a really good service dog. My friend got her trained for emotional therapy services and does not always bring her out in public with her. I gave her a long lecture on how not to act in restaurant/bars if she brings her in with her and how she can avoid being treated like an asshole if she does certain things. Like, only bring your dog out to those places in her vest... or if you forget the vest have her certification card on you and ready. Approach the person working before being sat/ordering/etc and say "she is a service dog, here is her card, we will sit anywhere that is most convenient and safe for both your employees and us."

She was amazed that people did not do that in the first place. Technically we can't even ask you for any of that information but it does make things a hell of a lot easier when you are actually a decent person and understand its actually a health code violation if it isn't a service dog and we can get in a lot of trouble if we didn't try to take proper precautions.