Of my two best experiences so far, one is a graduate and the other one is an undergraduate ('mature student' at 25 - AW age but I think it's accurate).
Call me snobby or fluffy if you like, but I'm not in this just to empty my balls every now and again and a bit of intelligent conversation is the perfect mid-session interlude or end of meet conclusion. It also makes me feel a bit more reassured that this line of work is a conscious choice for them rather than a way out of a bad situation; hence I think they are more committed to providing a good quality of service.
For me, sex in the absence of any kind of interpersonal connection is no better than masturbation (but then I am absolutely excellent at wanking, so it's all relative).