The reasons for living here are somewhat complex. The first one is the foresight of Dong Tianyu and his father, Mr. Thompson, and the second is that they have more contacts in the West District than in the East.
Other than relatives in the East District, there are very few friends of Hai's father. Due to the fact that his previous company was in the West District, many of his colleagues bought houses there.
So even now in this subway station shelter, Hai's father has many acquaintances. If they were to move to the community shelter near his home, they would know even more people there.
However, compared to the Thompson family's early occupation of a good area in the shelter, they didn't know where they would be placed if they chose to reside at the community shelter.
So Hai's father thought about it a lot and ultimately decided not to use the subway network to travel to the East District to reunite with his family.