Why? Reread the title of this post.
Come on. If he couldn’t sell that turkey even after he became a successful and famous writer, it ain’t worth buying. And don’t give me any ‘too embarrassed of his earlier foray into fantasy’ nonsense, either. I write books now. That manuscript would have been cash on the barrel-head for old Johnny, there. And do you know how much an embarrassed dollar’s worth? 100 unembarrassed cents.
If Steinbeck didn’t want anybody to see it, it’s got to be too bad for words. I know that this isn’t very romantic of me, but: some things are buried for a reason. And some graves, you just don’t poke.