No there are not certain types of dogs for service dogs versus companion dogs. Let me ask you a question, how does an employee know if the animal is a service dog or a companion dog? My understanding is, due to the current laws, an individual does not have to show you anything, just state it is there service dog. With this being said, if I came into Walmart with my dog, so I didn't have to leave it in a hot car, and you approached me with the question, "is this a service dog?", I could answer yes and be on my way. I hope to have more definitive answers when I am doing my research.
