Ultimately, life in both Ithaca and Sparta show the hallmarks of a shared underlying culture. They are both warrior-aristocratic monarchies that employ the use of slavery. Additionally, they share the same expectations concerning hospitality and generosity toward guests, with Menelaus and Odysseus holding the same values and assumptions concerning how guests ought to be received.
For all of this, however, Ithaca, unlike Sparta, is a society in disorder, due to the absence of its king. Thus, we observe the predations of the suitors, who have stepped into the power vacuum, insistent on marrying Penelope and taking kingship over Ithaca while exploiting those cultural expectations regarding hospitality. In this sense, Sparta and Ithaca can be understood as foils to one another, with Sparta representing a functional aristocratic monarchy, and Ithaca the dysfunctional aristocratic monarchy in distress.
At the same time, two additional aspects should be remembered: first that Menelaus himself speaks of his own struggles after leaving Troy, and secondly that Odysseus does return to Ithaca, slaughtering the suitors and taking back power. In this sense, the quality by which Sparta and Ithaca can be understood as foils to one another takes on an additional dynamic, with Sparta representing a potential vision of what Ithaca will become with Odysseus's return.