This.  I don't mind revealing how much fiat I have (paycheck to paycheck; no more than $2k at any point in time,) but when it comes to BTC, and how much I value that BTC, as far as anyone's concerned, I don't have any.  At least not on this computer, or any other computer that may or may not exist.  Also, it's easy to steal BTC; you can do it anonymously, over the Internet, without any repercussion.