Thank you for your synopses. The Joads experienced impersonal brutality from institutions, less "exploitation and discrimination" from "those who are supposed to help" and more inhumane indifference from institutions generally. Individuals might help where they could; institutions of that era simply ground people like a machine. Interpreting 'Grapes of Wrath' as a story of 'discrimination' seems odd to me. Brutality like what the Joads experienced was common for Mexican, Filipino, Chinese, Japanese, and other farm crews. I don't read Steinbeck as being sympathetic to banks forced to repossess farmers, or wealthy landowners 'forced' to burn their excess crops (even as other people starved) - rather, Steinbeck questions whether we must tolerate such dehumanizing structures. In even bothering to ask that question, Steinbeck's book became an enormously controversial piece - but the question remains important today.