Warning: lots of spoilers. But then, this movie isn't entitled to protection.
In both the book and movie versions of the Nazi-literacy-kitsch product "The Book Thief", Hans Holberman and his wife Rosa take in a 20 year old Jewish refugee because his father saved Hans' life during the first global war. Thus the potentially most interesting aspect of Holberman's actions is emasculated: he owed the guy's father. And thus the psychological perversity of this entire story is accentuated. He is repaying what is due. If someone is nice to you, you should be nice to them.
There were many people who took in Jews during the war-- not nearly enough-- but the percentage of them who were "owed" something by the people they took them in was undoubtedly ridiculously small. That's not why good people did a good thing. It's not why people risked their lives to help others. Do we really need another movie to tell us that we are essentially good--nay, saintly-- when we merely repay those who we believe owe us something?
It's psychologically perverse, because if Markus Zusak had the ability to penetrate the surface of his own constructions, he would have revealled just how fraught with moral ambiguity such a relationship would be: the Jew is asking the Holbermans to risk their lives on his behalf. The Holbermans are not idiots: they know that as perverse as a refusal would be, Max, the Jew, is also forced into a horrible position, that of burdening others with enormous risk for his personal benefit. It's the Nazi-kitsch equivalent of the stranger who rescues the toddler from certain death in traffic as the mother has dozed off in the playground. In Zusak's vision, the mother is eternally grateful to the stranger, and the stranger feels entitled pride in his achievement. But a real mother is not going to be eternally grateful to someone who makes her look like a terrible mother. Better yet-- she might be, but she would certainly be aware of the fact that her gratitude is not unalloyed.
When Max, who was forced to leave the Holbermans because of a stupid act by Hans-- for which the novelist forgives him instantly-- is marched through town, Liesel defies the German soldiers by racing to his side, in a scene reminiscent of James Garner climbing over the beds to get to his beloved Allie at the end of an equally overwrought story, "The Notebook", where the nursing staff find both of them the next morning, dead, in each others arms! This scene reeks contrivance: Zusak is desperate to clobber us over the head with just how utterly saintly Liesel is and he doesn't trust his reader to get it: she has to do something patently absurd, instead. The only thing missing was rain.
Graham Greene, better than anybody else ever, pointed out the essential narcissism of stories like this in "The Power and the Glory", and the damage they do to our understanding of good and evil. When we measure real actions against melodrama, we will fail to recognize the genuine heroism of people who were smart enough not to attract the attention of the Nazis when you are hiding a Jew in your house. Zusak wants it both ways: he wants you to wallow in the impetuous generosity of Hans Holberman when he can't stand to see the suffering Jews marching through town without water or food, and then he wants you to forget how foolish that action was by refusing to describe the conversation Hans must have had with Max in which he had to explain why he had to flee the house, to certain death.
It should be added that I think Zusak thinks the Nazis didn't have much use for reading. He doesn't make much sense of the fact that Liesel's act of "subversion" is to learn how to read-- the Nazis loved education, literature, science, and music. Yes, she takes a book from a book-burning, suggesting that she stands against censorship, but it isn't developed into anything. The books are rather random and irrelevant, and Zusak doesn't make anything of that either. The Nazis, of course, loved culture. They were enthralled with Schiller and Goethe and Wagner. Why does Zusak act like Leisel's reading is an act of subversion? Other than an appeal to that kind of nebulous dignity and intelligence we attribute to ourselves for loving literature?
The ultimate subversion is this: antiseptic accounts of Nazi resistance don't do anyone any good if they miss the point, that people who resisted Nazism were not always adorable and those who loved Nazism were not always repulsive.