Buying an assistant is like an in-game purchase. The jam's organizers said to give the player a reward in the full version of the game, and not to give anything in the jam. So you won't see anything here.
Then you need to make this clear, right now, it says
Get <> from Earth!
The <> assistant wil help you: loading and unloading the stack twice as fast!
[TAKE!]
[No, thanks]
Why would you NOT take this? instead it just looks broken as its not a "oh, this costs (currency you don't have but can work towards).
Several players must have been eager to play the updated version, judging by the number of dislikes. So, I'm sharing links to the full version:
https://playgama.com/game/mars-colony
https://lagged.com/en/g/mars-colony
https://www.y8.com/games/mars_colony
https://yandex.ru/games/app/471073