"Because privacy isn't about something to hide. Privacy is about something to protect. That's who you are," he said. "Privacy is baked into our language, our core concepts of government and self in every way. It's why we call it 'private property.' Without privacy you don't have anything for yourself."
When people tell him they don't fear surveillance because they have nothing to hide, Snowden says he tells them: "Arguing that you don't care about privacy because you have nothing to hide is like arguing that you don't care about free speech because you have nothing to say."
https://www.businessinsider.com/edward-snowden-privacy-argument-2016-9