Or people who don't want to have a GM-sanctioned wedding, or Galka+Galka couples, or whatever!
Feel inspired by one of the most creative things I've ever seen anyone do in this game (56kers are warned, complete with "naughty mithra pics" :3):
http://www.livejournal.com/community/finalfantasy11/1358996.html#cutid1
Anyone on Bismarck ever hold such a ceremony? And if so what did you do? ^^ It's RPing to be sure, but I think this kind of fun appeals to everyone, RPer or no.