Most of the people I have discussed this with come up with the question "Why are you afraid of being watched if you are not doing anything wrong?". My answer is always the same: Lets put a camera in your shower. Lets face it, each of us have certain things that we would like to keep private and being law abiding citizens in a free nation such as ours we should have the right to do just that.
Here are some of the aspects of privacy and what it would mean to not have them:
Without this your emails, letters, bank statements, love letters, perfomance reviews would be public.
Without this anyone would be able to do any genetic and drug tests they want.
Without this anyone would be able to walk into your house, place of work or anywhere else they please whenever they felt like it.
Its not anyone who can do these things but just those who have the authority right? Lets not forget the famous proverb: Quis custodiet custodes ipsos? ("Who watches the watchers?")