Regarding privacy:

1. People generally do not live in glass houses. Windows have blinds. Doors can be closed and locked.
2. Snail mail is usually in sealed envelopes.
3. Most people do not like knowing that they are being observed, don't like cameras pointed at them. There are laws not to video or take other kid's pictures without their or their parent's permission, depending on where you live.

My favorite one, even though I am not American is still the one that ends with "shall not be infringed."

Opened a can here ...