Service dog tags

Question
I heard that if you have a service dog tag for your pet that they will travel for free(on planes) is this true?
I have a mini dachshund that I am very attached to. She's not technically a "service dog" she hasn't been trained ect. But I went on to usservicegodregistry.org and registered her if I get the id tag for her will it then be ok for her to go in stores and restaurants with me(obviously only if she is well behaved, and travel for free on airlines. I registered her as a therapy dog  because I moved to a new state and got her and I honestly feel like with out her I would definalty suffered from depression, I am deeply attached to her and feel better whenever she is with me.
Have I done anything wrong by doing this?
Thanks.

Answer
Yes, you have done something both legally and morally wrong.  If you attempt to pass off your dog as a service dog to defraud the airlines, you can be charged with fraud and theft.  Registering your dog with the US service dog registry does nothing to make your dog a service dog and "proves" nothing to anyone since the registry is not generally accepted or used in the service dog community.