Don't most people know at work, we are not ALLOWED to answer how much money?

The internet has practically removed the concept of "none of your business" from our culture. Look at any social site and you will see a regular bombardment of in-your-face info that is nobody's business. Where anyone came up with "the people's right to know" is beyond me. No one has the right to know your business. Asking such a personal question is rude and inappropriate. You are right to dismiss the question as invalid.