Aaaarrrggghhh! Did you ever try to look up "shinola"? It doesn't exist!
How can something that doesn't exist be a basis of comparison to shit?! It doesn't make any sense. :/ That being said, how did a statement about nothing gain such momentum and popularity as to become a common phrase? The vast majority of people know what the phrase means but have no idea what "shinola" means. Maybe it was just the alliteration of it. The way "shit" rolls off your tongue, so to speak.
