Yea, I suspect it has more to do with juice content than juice color. Color can be an indicator of content, but not always.
I wish more juice manufacturers would list a broad content. I don't need the recipe, just an overview. Something like:
Contains:
- disolved sugar
- alcohol based flavorings
- glycerin based flavorings
- powdered spices
- whatever... (I don't DIY, so this is a gross guess)
- total flavoring is 5% of total volume, the balance being a base of vg/pg in the selected ratio and the chosen nicotine strength.