As stated already, there are many different sororities and fraternities, so you can't lump them all into one group. I just finished my freshman year of college and am part of a fraternity, and I am extremely glad I did. Why? I automatically had a fairly large social group, and you are put in situations (not hazing though, at least not for my fraternity) where even someone like me who usually is shy and quiet is forced to step outside of the box. I made many close friends faster than I ever really have before. If it wasn't for my frat, i know i would have been a recluse and rarely left my dorm, but i was going out with friends more than i ever have in my life. Also, as i already stated, we are not hazed, you are forced to do stuff you wouldn't want to do, yes, but no forcing you to get really drunk, or spanking, or anything demeaning. (though there are other fraternities like that) Also, we are a Christian fraternity, and don't support going out and getting drunk and laid like some other frats do. Plus, even when there are frats like that, that doesn't mean ALL the guys do that.
I admit though, many do focus on such things, but that doesn't make them bad guys. Another con is the cost, but mine for example was relatively cheap, and alumni often offer scholarships, but some others can be 1k+ a semester.