I was thinking of a way that the game can reward long standing players with a way to get donuts for our boosters.
My suggestion is that at hideout expansion 85% a donut maker becomes active that takes 2 spots. It would have 10 levels that needs a lot of resources to expand and also takes time to upgrade. level 1-10 should take about a month. At level 10 it would produce 10 donuts.
At 90% expansion a second donut maker becomes active with the same heavy resource needs and time to build.
At 95% expansion a third donut maker becomes active.
To get to these levels of expansion the player would have to be in the game quite a long time and be active.