Why Can´t Americans agree on how they Greet Each Other?

Last night I saw Garden City. A romantic comedy for the 00s. Many times when I watch movies my mind wonders. In this case I focused on this: why is it that Americans can´t agree on how to greet each other? Is it a kiss, a hug, a wave of a hand, a hand shake? Watch an American movie and you will see all the combinations.

I don´t have an answer but here´s a thought. Agreeing on a greeting code seems to be exclusively an American problem. In any other society that I can think of people know how to greet each other. In Spain is handshake among men, two kisses between the sexes and among women. In Argentina one kiss between sexes right cheek first. In Switzerland three kisses. But in America? Watch an American movie and see. In Garden City they kiss in the mouth, they kiss in the cheek, they hug, they bow, they wave hands. Now why is this? Here´s a theory. If you went into a restaurant in LA, NYC, Chicago as opposed to one in Paris, Tokyo or Madrid and you were able to ask people who are dining there how many times have they had dinner before that night you would probably find out that in America people tend to dine with people they know very little. In a sense while other cultures build long standing friendships among smaller groups of people Americans “collect people”, on the average Americans see a much greater number of people they know less, the famous American Rolodex now replaced by the contacts in outlook. In friendships Americans see quality in quantity. But there´s a counterpoint to this and that is loss of intimacy. Americans very frequently are with people with whom they barely know and less frequently they are with people they know very well and that´s why I believe they have developed a whole spectrum of greetings that depend on the proximity they feel to this or that person.