Earlier quoted context omitted.
To extrapolate this, people have taken advantage of other peoples' weaknesses. Gambling, drug addictions, suicidal thoughts...everyone has a weakness that can be exploited. I reiterate your statement; exploiting that vulnerability IS to blame and should not be applauded.
Can exploiting human nature be a positive thing? If looking healthy to attract the opposite sex can encourages people to work out, is that exploiting our "simple" sexual nature? To me, pretending to have a girlfriend seems as deceitful as dying your hair. Now, I've never done either so I can't say for certain. Furthermore, if your perception of someone changes because they're in a relationship, then maybe you should…
It becomes a matter of semantics. Certainly human nature can be used in positive ways. There are techniques you can use to hack on your own brain. For example, if you want to become more conscientious and involved in improving society, signing petitions and donating to charities is a way that you can trick your brain into making you do so. Merely writing down statements and signing your name to them can actually cause you to change your beliefs.
But I don't know if "exploit" is the best word for that.