is the expression "above the salt" still used?

Funnily enough I heard it used recently when someone was describing a rather snobbish lady (a la Hyacinth Bucket, oops Bouquet.) The person said "She thinks herself quite above the salt."

Regarding salt superstitions : I was taught that when someone asked for the salt (shaker) to be passed to them, one should lift it and replace it where the other person could easily pick it up. (this repeated by other people if a long table, ok) the reasoning being that it brought ill luck to take salt from the hand of another person. "Take salt, take sorrow" the exact superstition words.
Anyone else hear this?
Any ideas why?