"Size-ism" (is that a word?) is most definitely a problem in schools around here. I see many, many rush booklets and a couple of years ago, I saw one sorority's page that featured a shot with several very large sisters. Given the fact that this was a competitive school and that rushees are only 18 or so, I told my husband that that sorority had just shot themselves in the foot. Maybe they were trying to make a statement about their individuality--who knows?
Anyway, I asked the PNM from that school about it a few months later and she said that sorority didn't take any pledges in formal or open rush.