[dekeguy]

Tarahopeful,
Well, maybe a little more than just that we use greek letters. Way back in the begining of the greek system the core curriculum of university studies was based heavily on the concept of a "classical education". A well educated student was presumed to be very knowledgable of latin and greek (some lectures were given in those languages). This was the case across the spectrum of studies from liberal arts to hard sciences, which themselves used to be considered liberal arts. Look up "trivium" and "quadrivium" for more info if you are curious. Social groups which formed the basis of our modern day fraternities adopted names, mottoes, and all sorts of arcane meanings which were predictably expressed in the classical languages prevalent at the time. Some professors considered greek superior to latin for scholorship so it follows that the students would seek to have the best for their organization. The letters stand for private words which have to do (usually) with the aims and purposes of the group. Is all of the mumbo jumbo necessary? Probably not. Is it fun? Oh yeah! Does it mean anything? Means a lot to me!
So, its an 18th and 19th century thing that enhances our ties to the previous generations of our brotherhood and that act like a focal point. Each organization has its own special meanings and thats part of what makes it all so interesting and, to me, rewarding. So, you really didn't go too deeply into the subject and what it is all about. Check out some of the articles on the net about the history and development of greek letter fraternities. There is some interesting stuff out there.