I think it is rude to ask how much a person paid for something, I was raised with manners and I use them.
You do not have to tell people who ask flat out like that, you know they know a price range that people pay for Yorkies, and all they want is to make a comment about it!
It's different if you are talking with the person and they offer that information on their own. That has happened to me when I have asked a Yorkie owner who their breeder was because I was looking for one. I would not make any comment to them about the price because I know that they are a pretty penny.I asked more about the breeder and how the dog's were cared for.