To put it simply, people who came from Sunshine Base was not really having a good time on City A Base because their previous foundation were all gone. The resources they thought looked valuable were actually nothing much for City A Base.
With the backing of the research institute and various researchers from several official base, the live in the official base was getting better and better.
It was incomparable to those private bases.
Even though it was not that easy to live in this current time, but it could be seen that the standard of life for many people in the official base has started to be higher and higher. Of course, there were definitely some people who were still struggling at the bottom, but as long as they were willing to work hard, they could still live.
Their survival instinct was what made them able to survive all these times.