It's an example of the seen vs. the unseen. What they see when they do this is lots and lots of clicks and lots of attention on social media, and that's interpreted as a win. What they don't see is all the more mature and informed people being swayed in the other direction since they understand that hyperbole signifies a lack of deeper comprehension.
Depends on the audience. Hyperbole won't convince anyone who fundamentally disagrees with you; you need a reasoned argument for that. But hyperbole can work wonders on people already slightly inclined towards your position but not yet acting on it.
Of course there's a deeper underlying reason in my case: I am very deeply cynical about "activists" regardless of their political bent. Left, right, up, down, doesn't matter-- I've long observed that activists are True Believers for whom the victory of a pet ideology is more important than truth or reality. It really is equal opportunity: I am about as skeptical of Greenpeace's latest claim as I am of the religious right's recent "abortion doctors are selling chopped up fetus parts" outrage.
I will take you seriously if you have a genuine grievance. Otherwise I see third party activism (moral outrage tourism?) today as largely a form of entertainment. It's something people do to feel morally superior and self-righteous or to be part of a "scene."
As a practical matter the forces that led them to negotiate it in the first place will tend to prevent that from happening, but control simply is not being signed away.
They make their own class everywhere, no matter their nationality.
As a citizen of the US with a certain employment profile, I believe that the TPP mostly benefits me. Which doesn't mean I support it, I don't have a strong opinion either way. I think much of the criticism of the process is fair, but I think a lot of people are also looking past the broader motivations of it (bringing countries towards the US before they go towards China).
You see, I don't see people in Chile wanting tighter IP/patent/copyright law, people in Chile also don't want to give their sovereignity to a random foreign court (like it happens with, say, Argentina)... but quite the contrary. Except, of course, for those who make money off these laws and treaties, because, for them, the TPP is most probably a winning bet. Why wouldn't them want to sue their own government to profit even more? Why would, then, they avoid treaties that force their own government to follow the rules of a foreign country that is so admired and beloved by rich people (and wannabes, too) like the US?