Commentaire sur La Genèse 47:21

ואת העם העביר AND AS FOR THE PEOPLE HE CAUSED THEM TO PASS — Joseph caused them to pass from one city to another city that they might be reminded that they now had no claim to the land. He settled the people of one city in another. There was no need for Scripture to state this except for the purpose of telling you something to Joseph’s credit — that he intended thereby to remove a reproach from his brothers because, since the Egyptians were themselves strangers in the various cities where they then dwelt, they could not call them (Joseph’s brethren) strangers (Chullin 60b).

העביר אותו לערים, a stratagem also employed by Sancheriv when he conquered the northern Kingdom of Israel and forcibly exchanged the populations of that kingdom with people from the north. (compare Kings II 18,32). The purpose behind this was to prevent uprisings by populations who had no roots in their countries and therefore had no good reason to start a rebellion.

העביר אותו לערים, he transferred them so that they should encourage him to keep the grain safe.