Do you know the story of Mr. von Osten and his clever horse?
They help us to communicate information more clearly, and they can make that information more memorable to our listeners.
To say that robots don't have feelings is literal, as well as figurative.
In fact, there are several reasons, the major one being that telephones completely remove any visual cues from the process of communication. Not only do we read emotional content off the posture of a speaker’s body and face, but language comprehension is aided by a subtle form of lip reading.