Per this story, the Dodgers sold over 53K tickets for the last game with an Ohtani giveaway but only distributed 40K bobbleheads.

The corporate reasoning: The increasing frequency of giveaways means sometimes sponsors don't have/won't spend the money to provide items to every ticketholder.

https://www.latimes.com/sports/story/2024-08-27/shohei-ohtani-bobblehead-night-tickets