Why do some people say sororities are "buying your friends?"

[Yoquierotacobel]

I hang out on another forum that is similar to yahoo answers. it's just not as bad and allows a little more user interaction. I have seen a couple of questions about sororities on the site and people always go on to say sororities are for people who have no friends and have to "buy their friends" or sororities mean you're buying fake friends or whatever.

Even though I haven't gone through recruitment, I definitely think people are so ignorant when it comes to things like sororities and fraternities.

I asked my sister and she told me that if you go through recruitment 'properly' then that means you treated the sorority sisters just like you would anyone else you are befriending. she said it's the same process as befriending the girl who sits next to you in Calculus because you're getting to know the people individually. The houses aren't going to invite you back or give you a bid based on what you want to pay them but based on whether you click with them cause you're going to be sisters for life.

But why do people say this?