Fink was a real person, mythologized like Crockett, hence the stories of their encounters. Mike Fink's idea of a good time was to try to shoot a cup of liquor off his friend's head. Then, one day, he missed.
Yes he did kill his friend, but he was somewhat more concerned about the booze.
Keelboats played an important part in the settling of the American west. Most of them sailed from Pittsburgh. The keelboatmen were notorious brawlers, given to gouging each others' eyes out, and other cheerful occupations.
They would have eaten a Methodist preacher alive.
But they could take a boat down the Ohio to the Missisippi and down the Mississippi to New Orleans. Look at a map, and you'll see how long a trip that is.