Let me get on my soapbox here for a minute, please:
An old fashioned comment about **PEOPLE** is that "breeding tells". This was a reference to high class families, and the gentility and manners expected of both adults and children from those families.
Class does not necessarily mean money, being high class is a way of looking at and dealing with the world. There are people with very little in the way of material things that are high class, and people who are filthy rich who are low class.
To me, this experience is not about dogs at all. Mixed breeds or purebreds, they are all the same as far as having a place in our heart and family.
To me, if you meet someone in a public place and they introduce one of their family members, the proper response is to greet that family member be it person or pet, and note a good quality and give a compliment. That is the class way to meet others, it promotes good feelings and friendship, and that is the purpose of introduction.
The woman's response was low class, not because she used the word mutt, because there is nothing wrong with having a mixed breed in your family; but because her response was not designed to invite friendship and interaction.
Breeding tells