My understanding of this practice was that if he loaned (not gave) a semi-valuable article to a person of very bad character, they would never revisit to return the item. So for a very small "fee", the Vicar could rid himself of unwanted guests. I laughed when I read that passage, because it seemed rather ingenious to me.

This novel does have a certain tone, which might be considered absurd, but he seems to have a good take on the foibles of human nature.