Anne, far from wishing to cavil at the pleasure, replied, "I can easily believe it. Women of that class have great opportunities, and if they are intelligent may be well worth listening to.

Could it be possible that Anne is a bit of a snob? "Women of that class" makes me wince. Especially since she seems to be going out of her way to rationalize Mrs. Smith's gossiping with the nurse. She then goes on to rationalize Nurse Rooke's gossip as something educational. It seems like there's an implied rationalization here, that Mrs. Smith shouldn't be afraid of her nurse's immoral gossip rubbing off on her, since there is an opportunity for wisdom of the variety that might wind up in the sort of book Mary Bennett would read.