I wonder if the rat comment is more a reference to size than appearance? I use people's comments as an indication of their intelligence and education level, knowledge of dogs, and personnal taste. What people say about other people's dogs tells me more about them than they would like me to know, I'm sure. You could always use those awkward moments to educate the offenders. "Oh he looks like a rat!" "Well, actually this breed was developed in England in the 1800's to kill rats and to help farmers rid their fields of vermin and to protect their crops. The Yorkshire Terrier was introduced in the United States in 1872 and the first Yorkshire Terrier was registered with the American Kennel Club in 1878, making it one of the first twenty-five breeds to be approved for registration by the AKC." So learn some history, and take the opportunity to educate people when the situation arises. Wikpedia excerpts:
Smoky (c. 1943 –
21 February1957), a Yorkshire Terrier, was a famous war dog who served in World War II. She weighed only four pounds and stood seven inches tall. Smoky is credited with beginning a renewal of interest in the once obscure Yorkshire Terrier breed. According to an Animal Planet investigation, Smoky was the first therapy dog of record. Pasha, Tricia Nixon Cox's pet Yorkie, lived in the White House during the Richard Nixon presidency. So don't be hurt by their ignorance, many people just have no idea what a great breed the Yorkshire Terrier really is.