I think the difference is just in "how". When it comes more easily to a person in a certain way, it's not as easy for others to discern when it's happening, which of course allows it to be more effective. And thus can tick people off that much more.

It is an interesting word.. of course everyone, every person on this planet with intellectual capacity, attempts to "manipulate" situations in ways they think they should, whether it be for selfish reasons, or on the grounds of believing something to be "for the better good". Everyone does it to some extent; sometimes knowingly and sometimes to some degree unwittingly. As I've gotten more in touch with my own traits in this area, I find that while I prefer to try to be straight with people (including with myself) rather than have to deal with the aftermath of being sneaky, old habits do die hard, and achieving balance between different kinds of equally valid progress can be a conundrum, at least for this old noggin. (Manipulating for results vs. letting chips fall where they may.)

Just my two cents.