Arguing that you don't care about the right to privacy because you have nothing to hide is no different than saying you don't care about free speech because you have nothing to say.
The NSA has built an infrastructure that allows it to intercept almost everything. With this capability, the vast majority of human communications are automatically ingested without targeting. If I wanted to see your emails or your wife's phone, all I have to do is use intercepts. I can get your emails, passwords, phone records, credit cards. I don't want to live in a society that does these sort of things... I do not want to live in a world where everything I do and say is recorded. That is not something I am willing to support or live under.
We all need places where we can go to explore without the judgmental eyes of other people being cast upon us, only in a realm where we're not being watched can we really test the limits of who we want to be. It's really in the private realm where dissent, creativity and personal exploration lie.