The difference between a local and an outsider in the Hamptons is generally quite easy to point out. And I'm not talking looks-wise, I'm talking drinks-wise. The locals know just what to drink out East, because they have been doing so for years. We've gone undercover to pick out which spots in the Hamptons have cults that worship their one signature beverage, bringing to you a list of 5 cocktails you must try before Labor Day rolls around.