I would say that Steinbeck was trying to highlight how important it is to work towards solutions to social problems which will positively impact not just YOU or YOUR family, but the greater good. A lot of the symbols in the book have far reaching, metaphoric allusions - like the flood, or the parallels between the Joads and the Israelites - that support that whole Bible-esque "we're in this together, so we'd better do the right thing" theme. There are lots of others that come to mind, but I think you can sum it up with saying that the book has a very obvious and strong social message.
That's of course purely from a philosophical point. From a practical point, he may have been trying to simply bring attention to the plight of the real "Okies" which was largely undocumented at that time.
Whatever the case, It makes for a very interesting narrative even if it has been proven not to be historically authentic in too many ways. I think you can easily infer that Steinbeck meant for it to be taken very literally and "read in to".
I think newspapers are less important to people my age than to those in older generations because we grew up with technology, thus relying more on it than newspapers books etc. Older generations did not have much technology as we do.
