This resting system seems quite easy to scale by difficulty level:
- If you want to play in Story mode, resting would be easy and cost maybe 10 food points.
- If you play at medium difficulty, resting could cost 40 food points.
- Hardcore D&D stetting might put resting at 120 food points.
- Nightmare mode and you'll need 240 food points for a night's rest.
No toggle required, just tie the cost of resting to the difficulty setting that players choose to play at.