Basic human interaction is not manipulation. Every person who attempts to gain something by dishonesty should always be held accountable.
Every person attempts to gain something, even if it's only attention and validation. Therefore, the moment you're looking to gain something out of an interaction, you will look for ways to manipulate the situation. This can just be something like making sure the sun is at your back when you're facing someone, so you can see their expression but they have difficulty seeing yours. Women putting on make-up are manipulating their appearance. Combing your hair over the bald spot is manipulation to appear having a full head of hair.
You may even do these things 'unconsciously', although most manipulation is rooted in nurture and experience.
The main problem is that manipulation is seen as 'dishonest' by people who think in absolute terms of right and wrong. If you dress above your actual social standing to impress other people or even women specifically, you are manipulating the situation. If you work in an office and talk with a posh affectation to hide your blue collar background, you are manipulating the opinions of your audience.
If a stand-up comedian makes a provocative remark to draw your attention to something, he's manipulating your feelings, but is that bad? Or even unexpected?
Every person on this board who had a hand in seducing a woman will have manipulated the situation. Comes with the territory.
That's why my first question pretty much always revolves around 'cui bono'?