That's fine as a post-hoc explanation but I just don't think it really makes any kind of intuitive logical sense.Denizens of the said station have residency permits. Mercenaries don't, and if the do not behave, they get shot at
There are always a plethora of plausible explanations for why something could be some way, but in any situation where the vagaries of the in-game fiction appear to contradict common sense, it is good practice to signpost and then handwave the contradiction in some overt way.
The fact that none of the various play mechanics, voice clips and flavor text in the game do anything to point to why things are the way they are, is an indication to me that there's a bunch of people working on this game and they're shooting from the hip without a strong unifying sense of what they're building and what it means. I think everything could be explained by your somewhat bizarre "residency permit" explanation, but I strongly doubt that any of this has been thought through like that.