Why go greek?
Some people argue that going Greek is simply buying friends. Others argue that those who join fraternities do so simply to party or have a good time. The concept behind Greek letter organizations, and the reason they have spread across the country and become entrenched in collegiate life has nothing to do with money or wild dance parties that stretch until the sky blushes with the first lights of dawn. Fraternities are built on a foundation of brotherhood, the bond between men who have lived, worked, and played together. The fraternity experience is an experience of sharing and growth. It can take different forms in different chapters from cross-country road trips to marathon study sessions.
Of course, road trips and study sessions can happen without a fraternity, so one might ask why go through the trouble of joining if similar experiences can be had without wearing Greek letters. In truth, those non-members can easily have many of the trappings associated with Greek life like parties, and road trips. In fact, nothing is stopping motivated students from buying or renting their own house. So why would anyone want to join a fraternity?
One could ask a parallel question. Why join a sports team? You can get 5 or 10 people to play basketball, on any given afternoon. Everyone will have a good time, and the game can be played. But a player with moderate skills probably won't improve his game that much. If he joined a team with more experienced players, and coaches who can advise with experience and distance a player would most likely improve over the course of a season.
What Greek life offers is the opportunity to participate and benefit from more diverse situations and better-organized activities than would be available to a group of neighbors within a residence hall. Greek organizations develop leadership ability by placing responsibilities on their members for planning and executing social, philanthropic, and academic events. While a group of friends can plan events, a fraternity has the organizational structure and economic power to simultaneously plan a series of days helping out at a local charity like the Ronald McDonald House, while planning a formal, a party with a sorority, and helping members study for classes by encouraging brothers who have previously taken a class to share some insight, and study together; but only if they benefit from group studying.

