Human beings have a need for grouping, as well as belonging. It is only natural for individuals to look for groups in which to belong. Of course, this sort of relationship is suspect to some observers, as it is based solely upon arbitrary criteria discovered during RUSH functions, for the most part, and not on any sort of foundation that was created over time. Drinking is considered commonplace among fraternity and sorority members. However, the logic that associates drinking and partying strictly with the greek system is flawed.
Most college students engage in some form of partying and drinking.
The fact that fraternities and sororities appear to do it more than other groups is directly related to the disparity in resources available to greek students and non-greek students. With the amount of inviduals and money on hand in the greek system, as well as the capacity of their dwellings, it should not be a shock that drinking and partying is raised to such an extreme level. There is also a sense of community that develops when individuals party together. Many college and professional athletic teams drink together as a form of bonding. People in the military can often be seen out on a drunken binge, bringing their unit closer together.