Not that they’re liars. Just that they will all say very similar, generic type things.
She can write in her personal description on the resume that she’s outgoing, etc. So we’re back to the question of why is it better to spend time calling up a bunch of people to learn information that you could have spent five minutes reading on the resume. (To be clear, I don’t think that you should NOT call references– but I do think that a personal statement should be included.)