1)Some of my co-workers are in sororities, they work their a$$ off in the summer to save for their dues and other expenses.
3) I think it can help in some cases. I think it did in mine. The current president at the time I got my bid, not only went to my high school when I was a freshman, but she came back to substitute teach in my senior year. I have skipped formal rush. But, a few weeks later I attended a retreat for leadership training, she was in my cabin and remembered me from subbing. She invited me to a few COB parties. I got my bid a week or two later.
IMO I think that had a very big effect on my outcome. I guess it pays to be nice to some of your substitute teachers.