Cryptografy is what they do in spy movies with secret messages. Cryptography is meant to make it impossible for third parties to read things that are none of their bussines. You may be a lawyer, a politician, a political activist, a doctor, a priest, or you may just be concerned with your privacy.
Privacy is a fundamental human right.
You shouldn't be ashamed for standing up for it. And if Big Brother knows, your neighbours will very,very soon. Also cryptography is a vital tool in securing computer systems and financial transactions, securing copyright and patents. Some governments are planning to allow weak cryptography for these purposes, so that governments can break the code. And the mob has just about as much financial and thus technological means as a medium size country.