I lived and worked in a forest for a couple years. Probably took more slashes against trees than porcelain during that time. I prefer it, much more sustainable and probably more sanitary than your average toilet.
I do a fair amount of camping nowadays, have dug many holes. Rather enjoy the connection with the earth during the experience.
On a long hike, if you are drinking enough, then you're gonna have to take several breaks.
These places don't have toilets, adding such facilities would greatly detract from the whole point of being there.