The next line kind of makes connection between the two:
"We are hardly less primitive: why do we persist here in answering the telephone with the most unhelpful "hello" instead of our name?"
Implying that giving away your name to someone who doesn't know it yet is a similar kind of superstition, but its definitely a sane safety measure, as we know today all the crazy examples of what social engineering and elaborate scamming can do.
