"Just" short for justice is a finicky concept. As technology improves what can be considered the boundary for privacy begins to falter.

In a photo someone else posted? Your privacy is gone. Connect to public wifi? Your privacy is gone. Ping off a cell tower? Your privacy is gone. One of your relatives use ancestry.com? They can trace you to any DNA found even if you aren't in a criminal database.

Point being, you are not in control of your privacy. Far from it.

One doesn't need to give permission to join the pool of public data. In fact it requires significant effort to avoid it and in rare cases retract information added to it. A right to privacy is usually considered just. However, as our technology improves and it becomes easier to link disparate sources of data together, that right to privacy is eroded. Potentially even sold for a pitiful sum.

Don't get me wrong though. It's all a net good. For most of us, privacy is an incredibly cheap price to pay for the boons we are getting in science and technology.