When people argue against privacy rights by saying that they have “nothing to hide”, it’s probably true. Their lives just aren’t important enough to warrant a need for privacy. Privacy is about concealing something, or more accurately, the right to keep something from being observed by others. It’s not about keeping something secret, it’s about freedom from other people having access to it. In this way privacy is not a positive–an action taken to conceal–but a negative–a denial of access.
But privacy only really matters when the thing in question has any value. People don’t care about the state listening to their phone calls or reading their email because those things just don’t have much value, neither to them, nor to the state. There is no point arguing with such people on privacy rights because they themselves don’t actually need it–and that’s not because they undervalue privacy, it’s because they don’t value anything of theirs highly enough to warrant it.