I'm sorry that you had to deal with the ignorance of those kids. They need a little more training in the customer service department. Your Koda looks like a pure bred yorkie to me. I guess that they're use to seeing people come in with the tiny ones and they've stereotyped how a yorkie should look.
Shame on them and how they were behaving. I don't blame you for being so upset and you better start complaining. NO ONE should have to put up with that kind of abuse!!!!