Famous for purity! It's the most chaste candy you'll find. Somehow I doubt that the nation's finest creamery butter was diverted to hard candy that sat on the shelf for a year, but let them boast. Note how Cellophane is capitalized - possibly because the substance became much more popular and visible after the DuPont wizards figured out a way to make it less susceptible to moisture leakage. The candies wouldn't stick together: that's the pitch.