People don't change

The Grapes of Wrath is an American classic and was first published in 1939. Here is a paragraph though, that I did not expect to read:

"The doors of the empty house swung open, and drifted back and forth in the wind. Bands of little boys came out from the towns to break the windows and pick over the debris, looking for treasures. And here's a knife with the blade half gone. That's a good thing. And - smells like a rat died here. And look what Whitey wrote on the wall. He wrote that in the toilet at school, too, an' teacher made 'im wash it off."

Such a paragraph would not be out of place in a novel set in the twenty-first century, because people don't change. Houses are still left empty and boys will always be boys.