To me this song is a typical shanty style. The instrumentation, style of singing, humming, "hey heying" in the chorus and general atmosphere fit this genre quite well. Sea shanties were generally sung as work songs, helping sailors perform actions on board that required group effort like hoisting the top sail or the anchor but have later evolved into maritime theme songs, not necessarily meant to help during work but just to tell stories about sailing in the old good days. Wikipedia has a nice article on this:
http://en.wikipedia.org/wiki/Sea_shantyI wouldn't be surprised if traditional British shanties were the inspiration for MK to tell the story this way.
Interestingly, another song from MK's repertoire that could be considered shanty (although this time not sea shanty) is Railroad Worksong.