Question: What was the purpose for the tall tale of paul bunyan and babe the blue ox? 

Answer: i"Tale Tales," whether those you mentioned or the many written by Mark Twain and some of his contemporaries writing in the 1800's were merely to entertain, and surely they do just that. Twain was noted for his tall tale stories such as "The Jumping Frog of Calaverus County." Read them and enjoy!!
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