Judge a People by Their Language?

Often people seem to judge one another by the language they use, decrying them to be 'ignorant' or 'snobbish' for simply including, or not including, certain words in their vocabulary. Words such as "ain't" or "y'all" seem to instantly cause some people to decide the user is ignorant. Other times, when someone uses a word out of the common vernacular the opposite happens and and they are seen to be 'looking down upon' the people they just used that word with. Examples here are a bit more difficult for me as I enjoy being around people that try to use…