From Hard Choices, by Hillary Rodham Clinton, published 2014:
[ . . . ] Twenty years ago, American women made 72 cents on the dollar. Today it's still not equal. Women also hold a majority of lower wage jobs in this country and nearly three quarters of all jobs in fields that rely on tips like waiters, bartenders, and hairstylists--which pay even less than average hourly work. [ . . . ]Comment: Anyone, and everyone, can do something about this: Tip generously for good service.
And spread the word. Thank you.