How about the so-called "Throne Room?" (Was that for the occasional "Evita" who got to sit up, though dead?) And how about those magazines or storerooms with all those amphorae? And the frescos depicting people outside palaces, moving about? If these palaces are NOT the palaces (of the living royals), where ARE those palaces?
By the same token, where are the palaces of the Egyptian pharaohs? Many of their tombs have survived, while the palaces are long gone.
Food and frescoes were put in tombs, likewise such thrones are found in carved subterranean tombs in places around the Mediterranean, and no one suggests the King sat there before death to lay down laws.