That is, of course, because the documentary is about penises - specifically, those in Iceland's penis museum. And the contest between two dickheads who each want theirs to be the piece-de-resistance in a collection that so far does not include a human sample.
I caught this movie two Fantastic Fests ago, and it delivers - the "USA #1!" attitude is never more absurdly skewered than when it's looking at a guy who's actually willing to chop his cock off in order to beat a dying old man to the organ-donation punch. What a wiener.
Needless to say, the trailer is totally NSFW, though it shows no actual human schlong.