Because mining takes excavation.
This represents the need to station people in mining areas long-term. Do you understand how dangerous this is? The land has been occupied by demons for a long time now, and any mining site, no matter whose jurisdiction it falls under, could face the threat of demons at any moment!
Just consider, if the Alliance really agreed to Rocky's request and allotted him a mine, it would not only mean that Rocky would have to manage and mine this site but also that he needs to defend it against the threat of demons!
In Elder Farey's view, Rocky clearly didn't have this capability, because the attacks of demons were never minor skirmishes. A gathering of dozens of demons was merely a scratch, hundreds appearing together was the norm, and even thousands emerging at once were not unheard of.
