I actually met one of these people who was just in it for the trend, I was watching her (She is 16 BUT is a bit of a problem child even at 16) She had her "Girlfriend" over which was ok with her parents (they didnt know their daughter was bi)
So we are siting in the front room, I was on a reclining chair, One was on one side of the couch, the other on the opposite side... They were holding hands, and well I said "Are you two just close friends?" And the girl i was watching said "No we are together."
I responded "AWW! For how long?"
the girl I was watching responded "2 months."
I asked if it was just a phase? and blah blah blah, coz I have seen it before. THEY HAVE NOT EVEN KISSED YET! You cant be in a relationship for 2 moths and not even a peck. Those two after that convo were so awkward with each other. I mean to me, thats trying the trend >_<