Hermione did not use obliviate on her parents. (Spoilers just in case)

I read the books many times before i watched the movies (also many times). Its only now im re reading the series. And this really surprised me.

Just last night i started reading deathly hallows. And it was not obliviate that hermione used on her parents. I never realized this. When watching the movies I remembered that she messed with their memory in the books so it made sense that is was obliviate but in the book she clearly states she changed their names. Sounds like a confundus charm, to me. Then in the cafe she again clearly says she has never used obliviate.

Its such a minor detail. Why did they change it? The book version makes far more sense if she was to hide them from voldemort. He doesnt care if they remember a daughter he would torture them anyways.