Why did Hans offer bread to the old man who was obviously dying? Was his offer of bread for naught? Who calls him an "idiot" for doing this? Does Liesel blame him for Max's departure?

Hans offer of bread was greatly appreciated and a compassionate act.

The Jew stood before him, expecting another handful of derision, but he watched with everyone else as Hans Hubermann held his hand out and presented a piece of bread, like magic.

When it changed hands, the Jew slid down. He fell to his knees and held Papa’s shins. He buried his face between them and thanked him.

I see no evidence of anyone calling Hans an idiot, except Hans himself.

“Jesus, Mary, and Joseph.” Papa’s hands tightened on the splintery wood. “I’m an idiot.”

Max left because Hans had unknowingly drawn innemse attention upon himself and family by his act. Max left because he was no longer safe.

Liesel did not blame Hans.... she loved him.