The guys will be a lot more brutal and strict when it comes to pledging and joining. The girls on the other hand are a lot nicer and try to make each feel like they are all princesses. Sororities have the same type of functions and social parties as the guys but the girls tend to stick with fraternity guys for the parties. They try to match up with a local fraternity to make it like a brother fraternity. Fraternities are obviously not for everyone who attends college.
Many students like to focus on their schoolwork rather than build for the next upcoming party.
Many students like to meet a broader range of friends rather than just hang out with fraternity guys. The social gatherings I referred to earlier were not just social gatherings. They are keg filled parties that serve alcohol to anyone who wants to drink. You will find a lot of peer pressure within each fraternity and maybe this is not what you want to be doing with your college years. Fraternities take up a lot of time within your day, especially your freshman year.