The Mighty Princess Bempong

Alright everyone, I have a new library patron to tell you about.

An African woman comes into Northwest from time to time to get books, and her name is Princess Bempong.  Yes that's right, the system has her listed as Princess Bempong (not sure if that's a title or a name, but either way...).  She often comes in with her deaf servant who makes extremely loud, yet indiscernable, noises constantly.  Sometimes grunts and sometimes groans, and sometimes just hollering.  Here is the usual scenario:

Princess Bempong will come up to the counter and will make her servant ask for the books (which of course means just a lot of loud and embarrassing noises).  Since no one can discern this fellow's gestures or sounds, she gets frustrated and signs with him for a minute or two (while he's still grunting and groaning) and then finally writes down what she wants, and makes him hand it to us.  At this point we can usually help them, since what she writes down is an easy enough request.  But what I don't understand is why Princess Bempong doesn't just tell us what she wants...you see I know that she can speak because I've spoken to her on the phone and in person on more than one occassion!

I guess she just wants to make full use of her servant...who knows...