Maybe they think they won't recognize each other in the crowd of other Jeju honeymooners otherwise!
Well, they should just tie a balloon to each other, like all the other kids.
Don't these people take their cellphones with them in case they get separated?
From Dae Jang-geum: Sun-dol: "Are you trying to dry me up and kill me? Why do you say the same things over and over every day? Rather, come and hit me once! Aigu!" But then: Dr. Lazarus: "By Grabthar's hammer, by the suns of Warvan... You shall be avenged."