The older example of FaaS would be communal kitchens and dining rooms, e.g. college dormitories or kibbutz lifestyles. In these cases, people arrive to where food is being prepped for them; there is no delivery cost.

Particularly in the case of families, the notion that food delivery will ever become cheap enough to be a default relies on negating delivery costs. It may be so cheap to prepare food in bulk as to offset the cost of labor to prepare it; however, that says nothing as to the cost of labor (and energy) to deliver it.

If we ever do develop some kind of solar-powered delivery drone whose cost amortizes out to practically nothing over the life of all of its deliveries, then maybe yes.