It seems that the developers of both Pillars of Eternity and Tides of Numenera have got a real bug up their ass about people "abusing rest".
Personally this has never bothered me, and frankly I'm not sure if it happens because of lack of foresight on the player's part, or poor game design. (I suspect the latter, because I had to do it in Icewind Dale, and I planned all of my battles ahead of time like General MacArthur in that game).
So I'll accept that they're going to continue making it difficult for players to do this, but frankly I'm rather dismayed at the dull way they've chosen to do it. ToN only allows you to sleep in certain locations, and then for a price (bastards). PoE requires you to carry around firewood (I guess they didn't get the memo from the forestry service about only using local firewood to prevent giving destructive insect colonies a vector into other forests), and naturally this is the one item you can't keep in the stash, and it has an arbitrary limit.
So here is what I suggest they do instead. Allow the player to sleep anywhere, but add realistic penalties for doing so.
- Do not allow them to fall asleep until fatigue is over a certain level. Otherwise they just toss and turn and their fatigue continues to build at a slower rate. (they did this back in Ultima V, 30 years ago!)
- Have you ever heard of Exploding Head Syndrome? This is what happens when you fall asleep when you're in a state of anxiety. If you try to sleep in a forgotten corner of the evil overlord's sentinel, you could suffer a minor (but temporary) reduction in mental facilities and alacrity.
- If the player sleeps more than a given percentage of a day (for instance if they deplete their fatigue intentionally using booze or something so they can sleep again), they'll end up getting infected bedsores, which they'll need a doctor to treat.
- In addition oversleep will lead to grogginess, where mental and agility scores take a hit.
In general I prefer an approach where the designer doesn't say: "you can't do this", but instead says: "you can do this, but there's a cost."