Modern Family creator Steve Levitan justifying why, during a recent scene, the straight couple kissed but the gays didn't:

Two of the writers on our show who are gay were explaining their very different points of view. And one of them is very comfortable [with it]. The picture was shown of the two couples kissing in the airport and he said "I would never ever kiss my partner in the airport."

I wouldn't either. It makes everybody think you're Italian.