On a certain continent, nearly all kingdoms worship under the same pantheon. However, in the southern reaches the peoples take a much more...liberal stance on their Gods. Statues are nude, and very anatomically correct, and icons are often startlingly brazen. For instance, the icon of (insert name), the goddess of love, is an image of two nude twins embracing in a passionate kiss, signifying the love of both family and partner. This is a source of unending outrage and offense for the Northern churches, whose traditional and modest take on religion is constantly at odds with the near-blasphemous ideals of the Southerners. While this is not enough to provoke outright conflict, there is more than enough simmering discontent and long-held grudges between the two hemispheres.
Pirates' many bejeweled rings and piercings actually had a practical purpose - when the pirate or sailor died, the rings could be taken off as payment for a proper burial, saving him from a watery grave. This could be tied into regional culture, or made into a quest (The Pirate's Lost Rings, etc.). Also gives treasure-seeking divers another thing to look for besides crusty old chests.
Common for sailors to get lashings for punishment. Sailors would then get tattoos of god symbols on thier back so the thrasher was less likely to whip the symbol of the god.
Others say symbols bring bad luck. They draw the attention of the god and it could be wrathful.