The mistake would be reading Hacker News and walking away with the conclusion that because people don't post that reasoning here that it doesn't exist (and even then, you do find that does come up here on occasion). People with "nothing to hide" do actually believe that, and while they may not post it to HN for vigorous debate. The easy counterexample from history is the list of Jews kept by the Netherlands which was later used against them after they were conquered by Nazi Germany, but you'd have to interested in history to buy that reason. Some people simply shrug at the "if you don't have anything to hide then you won't mind me filming your bedroom" scenario as you being the creep in the equation. Some people just don't want the trouble and are fine with being surveiled because the powers that be are doing it.