Kind of related: Ellen Pao has said she has ended salary negotiations at Reddit to try to prevent gender bias.
http://www.pbs.org/newshour/rundown/reddit-ceo-ellen-pao-ban...
http://www.pbs.org/newshour/rundown/reddit-ceo-ellen-pao-ban...
I've worked in companies that paid 1/3 less than others (management consulting), many people knew they were paid less, but few people left. Jobs can often be sticky.