Are you seriously arguing that sleeping out in the nature, potentially with dangerous animals around you, on bear skins, with several friends (on the same bear skin?) is as comfortable as sleeping on a modern mattress in your home?
There have been studies that confirm sleeping outside results in sounder and healthier sleep.
I think about it in terms of germs. Yes, on paper it's more safe to sanitize everything, but in doing so we prohibit our ability to build defenses, and actually become less healthy.
In the same vein, maybe by sleeping on mattresses indoors all the time, we fail to build a tolerance to adverse sleeping conditions, and maybe get more sensitive to them too.
I knew of an old thai man who's face looked like he was 80 and his body looked cut and jacked. He also preferred to sleep with a thin mat on a hard tile floor with his wife in a house where there were multiple clean, usable beds to easily sleep on instead.
So if your body adjusts to it, it's definitely possible to actually prefer it.
Hard perfectly flat sleeping surfaces with just a simple blanket for warmth can stimulate the lymphatic system much like a massage can.
The worst is when you have an uneven surface, like when camping and there is a rock which even your (inflatable) roll mat cant dampen out, that makes sleep difficult.
My anecdote is that when I get migraine headaches, I have to lay down and try to sleep. I have to lay on hard ground. I can't stand being on a mattress for some reason. Maybe it's about feeling more control over the position of my body.
To me there is something deeply comforting about inertness. I hate the springyness in matresses so much I got a natural latex mattress, which I found out most people get because of allergies, but to me its like a kinetic sensory deprivation chamber- just absorbs all movement and doesn’t reflect it back.
Okay, and the sensory deprivation helps you sleep? I suppose that's generally what we're headed for. Turn off the lights. Set the temp to a certain level.
The hard ground isn't giving either, but you feel it. ;)
I also can't deal with pillows when I have a migraine. Though I can't sleep without something under my head. I usually just roll up a towel or something. As I said before, I think it's about having precise control over body position.
