Shoot the Moon (and more)

Recent almost-college-grad Fred Kitchen and his eccentric six-foot-four pal, Wheaty, pay off a poker debt with a prank — showing their stuff in the then-current fad of streaking.
Soon they are under arrest and in jail, killing time by playing cards with a couple of hardened criminals, unwittingly racking up a new debt... one that can only be paid off by participating in a bank robbery during a small-town festival.
Written as a tribute to the comic novels of his mentor Donald E. Westlake, Shoot the Moon is a fast, funny crime novel written early in his career by Max Allan Collins.