Martin Luther King Jr. influenced people. Gandhi influenced people. Mozart influenced people. Your favorite teacher influenced you.
Once the readers are drawn in, whether from base or nobler instincts, the book can try to influence its readers into being nice.
Only trouble is that it may push away those who are "already nice" enough to feel bad about manipulating people.
I think it's puzzling that so many people here attach such a negative connotation to "influencing." I mean, my partner made me really hungry tonight when they cooked dinner and it smelled great. It influenced me. MLK influenced people. Etc. etc.
BTW, Dale Carnagey changed his name to crease a false association with Andrew Carnegie.
So there is good reason to distrust Dale and his followers.