There is no such thing as "Marlboro Greek Life." There is really no need for it. Students find their way around the social scene without the help of a sorority or fraternity.
People intermingle among the tiny population, and there is often a great deal of partying that involves the whole campus. You could look at it this way: Marlboro's population works hard at their studies, and plays hard also. But there aren't specific groups in which they play.