Kenner stored a LOT of pre production material throughout 78-85 , Tom N ( a former Kenner employee with an interest in SW) was given a chance to "save" whatever he wanted within a 24-48 hour period when they had decided to clear it out and bin most of it.
It's hard to tell exactly how much of whats out there came from him but I would hazard a guess at 70%, the rest were found by bin raiders at Kenner dumpsters (collectors "stole" these unwanted pieces straight from the bins after clear outs) and other Kenner employees who either worked on the packaging or were involved somehow in creating the toys , most taken home as keep sakes.
These were mass produced toys from a huge toy company, its quite feasible that what seems like many (5 of the same proof card for example) is nothing compared to how many were actually produced, imagine a whole office of staff checking for changes on the same card etc, this goes for 3D prototypes as well - Tom once stated that he used to walk past bin fulls of first shots when he left work each night , those were binned.
