I'm probably closer to Radagast in terms of experiencing rural filth than most others here ever will be. And I'm old enough to remember the 1970s when it was normal to only have a bath once a week, whether you had an indoor bathroom or not. I also worked on my brother's travelling shop and we went to the really isolated farms on Saturdays. At one old farm, a couple had moved the bed into the 'kitchen', which was just a room with a range, a sink and a load of hens running round and pooing on the table/chairs/everything. The filth was spectacular.
As for poo, one day I was wearing my nice new brown M&S anorak while messing with my nan's hens and as usual carrying them round under my arm, ending up with my pockets full of dung. One of the jobs my boatmen ancestors did in the 1800s was load their barges with 'nightsoil' to spread all over the fields and grow taters and carrots in. Yum!
Has nobody heard of the saying "Muck for luck?" It's a way of laughing off the highly likely chance that you will get pooed on by a pigeon/seagull in the UK. If you're sat on the graveyard wall and enjoying a bag of chips and get divebombed you don't go screaming like a girl for antiseptic wipes, you just let it dry and then pick it off later. No sense in letting your chips go cold.
All of which is my way of explaining that rural filth was very much a part of life not many years ago, and a lot of us aren't even now that bothered by it, so it's not something I have to suspend disbelief on
one little bit to accept that anyone living in the middle ages or the wildwood might get covered in guano and muck.