Why do basic resource support zones not have building slots

[cerberus189]

This is more of a question out of curiosity and to see what others think. For some reason the support zones for food minerals and generator districts don't have any building slots. This to me is a little weird since they are the only zones with no building slots even their research support zone cousins have building slots. So I am just wondering what the reason is?

I think it would be nice to at least be able to build some trade buildings and food in the zone since they give trade jobs.

 

[VexacionRT]

I would love to put those buildings you get from the curators for archive completion in there...

 

[Ishyro]

It's probably for balance reason (can't put those trade buildings here), but I don't know if it was really necessary.

Or maybe just for roleplay and vibes, your planet is so devoted to 1 thing that it cannot do anything else.