In that first paragraph, you can also read it as a society for the study of the American Cancer, and it also makes sense. Unfortunately, it metastasized and any connected tissue gets infected as well.

I guess most immigrants don't need to learn the shibboleths, unless they suddenly get into money and want to join the upper class. It's about discriminating between the commoners and the rulers, that's why it constantly evolves, too. Need to regularly release new ciphers if you're communicating in the open with a trivial cryptography.