The ego is cunning.  It will use even the seeking-will-effort you mentioned to sustain/perpetuate its own movement-survival; to perpetuate the "striver-seeker." The ego mind "thinks" that it can set out to kill thought, but sneakily ego's sole interest is to perpetuate it. 
Gurus are well-aware of this cunning nature of ego-mind, and therefore don't intend to nourish it by feeding the "seeker-striver."
 

@Alexandar Edwards
Your question is coming from a certain level of consciousness: duality.
Your question is really about survival, not being or Truth. Survival demands constant manipulation. That is life. Improving society is a function of survival. Think of politics as nothing more than hunting squirrels in the forest to make sure you don't starve to death. That's what government is fundamentally about.
There's nothing wrong with improving society, just like there's nothing wrong with hunting squirrels to survive, but there is a meta-issue: your preoccupation with survival is keeping you from realizing that the world is an illusion.
What if one day you wake up and realize that all of this work you've been doing to improve society was happening inside a dream state? Such that slavery, racism, evil, nuclear weapons, science, and even your mother and father do not exist because they were just a dream? How silly would you feel then to have worried so much about all that stuff?
These are awakened people you are talking about it. To them, reality is just a dream. Nothing is serious. Whatever actions they take to "improve society" is just for shits and giggles. They are shooting at squirrels in the forest just for fun. It's a form of self-amusement. They are detached from it. They would not really care if the entire planet was nuked tomorrow. They would be just as happy. It would not be a problem for them in the same way that seeing the Earth get nuked on TV isn't a problem for you -- because you are conscious it isn't real to begin with.
All human suffering is unreal.
This kind of level of consciousness is difficult to fathom for someone who has not awoken from the dream. It is unimaginable that this could be possible.
The reason an enlightened sage is good at helping people is because he is already dead inside. There is nothing for him to fear or lose. The world does not need improving, yet there is nothing else to really do here but help improve the world. That is the paradox. But you won't understand this at stage Green. You need some enlightenment experiences to understand it.
P.S. Morality is a function of survival. Not Truth. The ultimate truth is, there are no problems whatsoever and evil doesn't exist. Yes... detachment is a very radical and counter-intuitive thing.
P.P.S. Advanced sages don't usually come out and say this so bluntly because they would be crucified by ignorant people for saying such things.