After writing that peice on the evacuation I decided to draw it out.
As you can see, the Moon has limited water and foliage making it less than ideal for large amounts of people. Also, those ships around are additionally carrying refugees. They ARE MASSIVE. Some about the size of a city. They orbit the moon using it to help protect against long exposure to radiation from the sun. Not every ship can fit back there safely and smaller ships are given priority over the larger better insulated ones. About 90% of the Refugees are on the Moon however, in camps located in the deserts of the moon or swamps.