I'd find out the different rules/regulations between a trained service dog compared to a companion dog - are untrained companion dogs given the same access as trained service dogs?
I found this:
"The Difference between:
Service, Therapy, Companion and "Social/therapy" Animals
Service Animals are legally defined (Americans With Disabilities Act, 1990) and are trained to meet the disability-related needs of their handlers who have disabilities. Federal laws protect the rights of individuals with disabilities to be accompanied by their service animals in public places. Service animals are not considered 'pets'.
Therapy Animals are not legally defined by federal law, but some states have laws defining therapy animals. They provide people with contact to animals, but are not limited to working with people who have disabilities. They are usually the personal pets of their handlers, and work with their handlers to provide services to others. Federal laws have no provisions for people to be accompanied by therapy animals in places of public accommodation that have "no pets" policies. Therapy animals usually are not service animals.
A Companion Animal is not legally defined, but is accepted as another term for pet.
'Social/therapy' Animals have no legal definition. They often are animals that did not complete service animal or service dog training due to health, disposition, trainability, or other factors, and are made available as pets for people who have disabilities. These animals might or might not meet the definition of service animals."
http://www.deltasociety.org/Page.aspx?pid=303
And:
"The Definition of a Service Animal under the Americans With Disabilities Act and Guidance documents from the U.S. Department of Justice have established two training requirements for a Service Animal. The first is that a service animal must be individually trained to perform tasks or work for the benefit of a disabled individual. The second is that a service animal must be trained to behave properly in places of public accommodation. Inappropriate behavior that disrupts the normal course of business or threatens the health or safety of others is automatic grounds for excluding the team from the premises.
Most animals, including but not limited to those labeled Companion Animals, Emotional Support Animals and Therapy Animals or pets are NOT service animals according to ADAs Definition, as they have NOT been individually trained to perform disability mitigating tasks. Thus their handlers do not legally qualify for public access rights. Typically these animals also lack the months of training on obedience and manners needed to behave properly under challenging conditions in places of public accommodation."
http://www.iaadp.org/iaadp-ada-training-requirements.html