Based on Spooky's experience with their previous games, the expected appeal of the Rick and Morty license, and their limited daily capacity, 750 was a good number for them to plan. They didn't know the 750 would sell out that fast. Just like PPS/CGC had no idea 1,000 MMrLEs would sell out so fast when they announced their first WMS remake at Pinball Expo a few years ago. I do respect Spooky for holding to the announced limit of 750 and not increasing it due to demand.