[JulianMorrison]

If your city's supermarkets can feed people with in-person shopping, they can feed people with deliveries as easily, it's the same number of people buying food.

[mishac]

That's assuming that every supermarket has enough delivery staff. That's not a valid assumption in many places.

[ddtaylor]

With an extra layer of logistics that will have failed because the delivery drivers or pickers are sick.