Why Was It Banned?

After reading even the first couple of chapters of this novel, theres no surprise that the famous Steinbeck book has been banned, but to be ranked 2nd of the most frequently banned books in the United States? There must be a reasonable explanation, but there must be some significance for it to come back. A book which holds the themes of harsh poverty, false hope, racism, sexism and death don't exactly sound like the most appropriate book for younger readers. But if these issues aren't understood before kids leave school, when will it be noticed?
Many parents have complained to teachers about their child studying this book for the following reasons:

• The use of the N word (which used to be a neutral term) referring to black people.
• Some claim  its derogatory towards African Americans
• Some claim its derogatory towards women
• Profanities
• Racial slurs
• Violence
• Absence of traditional values

Source

The beauty of the controversy of the book is that the book has been banned so many times because of this, therefore the literary work has been more closely examined and more ideas have been shared than if the themes weren't challenged. I think that if this book was not complained about before hand, it wouldn't be anywhere near as popular as it is now.

I can understand why parents wouldn't want their children to study this piece at school, however if a young mind isn't exposed to the truth of 1930s America, then will they ever understand this type of discrimination, this type of violence, this type of reality?