Obviously, we're all just speculating here, but why do we think there is a finite cap on food/rests? Merchants refresh their stock on long rests, and it's looking very much like they'll be introducing camp supply equipment packs for the purposes of rest, so you're not scavenging the map for bits and pieces of food - see here from the stream:

[Linked Image from i.imgur.com]

Value of 40 (so will be higher in stores due to mark-up, but nothing crazy).


We haven't seen these yet, but there are potentially other ways resting will be introduced in an infinite manner where it makes sense. Obviously the new resting system is just in its infancy, but we aren't sure if food-resting is the only option. For all we know, food isn't required if we're resting somewhere deem civilized or safe (i.e. in the Druid Grove). Alternatively, Resting via NPCs dialogues (think Planescape Torment) or Inns might actually be implemented now because they'll serve a function.

Lastly, there are also spells that technically fulfill the function of food do exist (i.e. goodberries), so that's might be another potential unlimited resources of resting.