Rabbi S. R. Hirsch comments on this (Bereishis 47:22), but really limits his observation only to noting that Moshe was not imitating the Egyptian law:
"Only the land of the priests he did not buy etc." Here we see a complete contrast, which opposes that theory which has become rooted in so many people's views, the Moses had learnt and adopted his legal and religious wisdom from the Egyptians. The supposed teachers of Moses, the Egyptian priests, possessed land, more, after the alteration in Joseph's time, were the sole owners of actual land, and besides had a fixed assured state income. Our Kohanim possessed no land at all, and had no income from state funds, but were dependent for their existence on the good-will and respect of private individuals. Had Moshe Rabbeinu been a "Moses" [self-interested priestly lawgiver] he would have made other arrangements for his own tribe.
This comment hints at the social implications of the different systems and the social value of the Torah's approach, but without elaboration.