Hm. EOLS, the problem is that most NPCs are full of hot air. I tried to point out their usefulness to her at some early stage, but she decided to then go and talk to some kid who said something about shorts. :/ I tried to convince her of the 'talk to everyone' thing, but that just sounded like a waste of effort to her.
And she's always really underlevelled for the Gym Leaders because she avoids as many Trainers as she possibly can. When I asked her why, she said 'I don't like battling!'. I told her she'd bought the wrong game if that was the case, but she just stuck her tongue out at me. Each time she complains about being underlevelled, I try to explain to her that all she has to do is go fight a bunch of wild Pokemon (ie grind just a few levels) but she seems to lack the patience for even that.