Let's get away from the "unable to be filled" metaphor for now. I still think it's applicable, but it's obviously not helpful in our current context of this discussion.
Possibly a more apt metaphor is the old Western movie set where there appears to be a main street of the town, but it's only a line of facades. The facades may be indistinguishable from actual buildings, but walk through them and you're in the desert. There's nothing there. It's an empty space. Likewise, the empty desires are nothing but attractive shells or facades. There may be bright neon signs on the facades with POWER, MONEY, etc, but there's nothing to back them up. To put it colloquially, "there's no there there."