Explain why Hepzibah upset at accepting money for the gingerbread being sold to the boy.

From the text:

“No matter for the money,” said she, giving him a little push towards the door; for her old gentility was contumaciously squeamish at sight of the copper coin, and, besides, it seemed such pitiful meanness to take the child’s pocket-money in exchange for a bit of stale gingerbread.