My knowledge of frats is fairly hazy these days. Still...
Fact: Fiction hasn't yet come close to the reality of certain fraternities. I've never seen any movie or book cover the ubiquitous "Let's burn a dead cat in the middle of the floor" scenario, while the group sings "Light my Fire!" by The Doors.
Or the strange quest to collect as many traffic cones (pylons) as you can in 45 mins while hanging out of the passenger-side window wearing clown's makeup (or other unmentionables). Don't ask what happens to the cones afterwards -- nobody really knows for sure.
Or the very unsociable business of "hogging" which I will refrain from going into detail.
And these are but a few. The stereotypes are not too far off, yet they often miss the mark.
Yet, there are some that are not rowdy and very ... er... solemn... I guess. Rituals that are handed down for hundreds of years... brotherhoods that have nothing to do with wild parties.
Others function as networking groups for after college.
Still others are based solely on nepotism... so and so's father or brother was a member, so you're automatically in -- which is stereotypical, surely...
I don't know if any of this helps, really... sorry.