Why is privacy desirable?

I like privacy, and it seems that occasionally we need reasons to defend what privacy we currently have been given. These are two reasons I came up with before getting bored of the thought exercise and never returning to it.

The working TL;DR I was able to come up with is:
There exists people who would cause you harm if they observed you performing some acts.

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Humans cover certain parts of their body for various reasons. Smarter people than me have explored and explained those reasons. One person offering one explanation said something like 'if humans were naked all the time, we would be having a lot more sex with a lot more people. Humans can't go around having sex all the time, it would be detrimental.'. Either they or someone else, or no one went on to say something like 'a lot of sex with a lot of people would spread more diseases, which harm the race as a whole and also the individual because itchy junk is bad. Also, we benefit from actively producing and consuming collaborative effort in society, and it's difficult to build out new processor architectures while you're busy banging all the time'.

Humans, like all lifeforms, consume energy and discard the waste product of that energy. When ridding our bodies of that waste, we often use orifices that have been covered. We pull our pants down to poop. If we didn't close the door when we pooped, people would see us more naked, and might want to have sex with us.

Therefore, privacy in the bathroom is important to those who want it.

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A Theif wants your money, so they observe your PIN when you enter it at an ATM. Then they steal your debit card.

People who have not been mugged typically feel safer and therfore happier than people who have just been mugged, regardless of the value of the stolen item.

If you had privacy when you entered your PIN, not only wouldn't you have lost money to an ATM withdrawal, but the Theif wouldn't have even bothered taking the card, because a violation of your privacy is required to use the card against you.

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