Offering a different perspective based on my school:
I swear, I honestly am not a big fan of freshman. At my school I'd say about 2/6 chapters had amazing retention. The rest usually were around total give or take 20 members while I was there. Many freshmen came in, had no idea about greek life, did whatever/managed two years (on average), and burned out. (Some disappeared as soon as initiation was done!) I think with older women, they think about it more and are willing to commit to it if they're putting themselves through recruitment. It's b/c they thought about it long and hard first about what they were doing. (That or they depledged and rushed again and the 2nd time and they did "better" and were very willing to commit). But once again, this was at my particular school.
(Three of my five littles and myself weren't freshmen and I must admit, we did/are doing quite well!
)
ETA: And regarding the "rules" and not wanting to deal with them...Oh boy! I can't tell you how many times I thought "I'm too old for this!" But I decided that I wanted to do it, and I had made my bed, so I sure did my best to lay in it with a smile on my face!