Twain loved to satirize groups of people for the express purpose of exposing their hypocrisy. Mrs. Watson (who considers herself a paragon of reform for wayward rascals) is depicted as a highly religious individual...and yet she owns slaves. Pap is a terrible individual, prone to every vice known to mankind, and yet he believes that he's better than the slave or anyone that has an ounce of black blood in them. In Huck's case, everyone's attempts to civilize him only serve to confuse him more about who he truly is and what he truly believes.
