I think a better solution would be to keep the late fees then after they totaled the cost of a new book send a bill to the borrower for the cost of the book plus and added 50% handling fee. If that is not paid within x number of days sell the invoice to a credit collection firm. The people that don't return books are in essence thieves and are impacting legitimate library users abilty to read books. May seem kind of harsh but I grow tired of seeing petty theft and shoplifting going unpunished.
