Privacy (or lack thereof) Justification

I know this is a popular subject, and I am a newbie so I haven't read all the discussion.
But anyway, I have a tale to tell, and a question.

I was reading the forums when I came across threads on the issue of being able to teleport to another users location. I hadn't known it was possible and thought the info was useful.

Later, in SL, I noticed that a friend (of the opposite sex) was online, but as is often the case she wasn't answering IM. Normally, she is asleep in a chair somewhere & away from her machine.

So, I went to find her, using teleport to her location on the map.
I caught her in flagrante delicto!
I must say I was just as shocked & embarrased as I would have been in RL.

So my question is this:
I have seen it said that you are looking at ways to modify the current system adding various privacy controls. But if somebody wants you to come to them then they can offer you a teleport.

Is there a justifiable use of this feature, something that would cause 'harm' if the feature was removed?
What is the justification for having this feature at all?

Most of us would never put up with this in RL, I don't think we should accept it in SL.

Finding someone on the map and just dropping by without asking *can* be a privacy violation, as it would be in real life. I think the polite thing to do would be to ask first, and if there's no answer assume either they are AFK or "indisposed".

That said, we're looking at privacy issues, including the option to toggle off your visibility on the map.