Aren't These Kanjis Too Hard?

Here's an array of kanjis that even native Japanese speakers aren't sure about reading right. Split into three level groups, there's 400 'read-hard' ones in the book.

Note: Most of the kanjis or the readings in this book are not on the government-issued List of Commonly Used Kanji, so picking up those in the book for your JLPT will be irrelevant.