I don't see how people are surprised that if they used Coinbase or other similar services, would get any sort of privacy out of it. The only way to have privacy in this world is if you accept payments in BTC, if you mined the BTC, or if you buy it over the counter, the rest of methods will always leave a track so you better be ready to explain the taxman what you are doing there. I have nothing to hide because all my bitcoins are of legal origin, but I just want to ask:

If you own BTC, but you don't report it and they never know until you sell them to buy some real estate for example, what would they say? You were committing a crime in theory by not reporting that you had BTC, so what happens when you sell them to buy a house and they realize you had them but never reported them??