What offer does Mr. Fox make to the other animals present at the feast and how will it provide them with safety?

At the feast, Mr. Fox proposes that the other animals' families come to live with him, so that everyone can utilize the tunnels leading directly to food within the three nearby farms. The animals happily accept, especially since they are tunneling animals that do not like to go out in the open anyway, and now none of them will have to do so.