Why should one wrap bread dough in a towel during the last rise, instead of some other material?
I've made sourdough bread a few times following the same ("beginner") recipe. After the dough rises overnight in a bowl you put it on a floured surface, fold it in on itself to shape it, and let it rise again for a few hours. For this final rise, the recipe says to take a bowl or bread basket, put a towel in it, flour it, and then put the dough in and cover it with the towel.
Why a towel in particular? I know we want to avoid exposure to air. A towel is porous in a way that a sheet of foil isn't; does the dough want a little air? Why not instead put baking parchment in the bowl, flour that, put the dough on it, and then cover the bowl with either a towel (if porosity is important) or foil (if it just needs to be covered and it doesn't matter with what)?
I tried to answer this question through experimentation; in one case I used the floured towel and in the other I used floured parchment paper and foil. (I haven't tried parchment paper plus covering with a towel.) In both cases, the dough stuck a little to what it was sitting on despite the flour. I didn't notice a difference in the resulting loaves, though I did them on different days, not side by side, so I didn't control for other factors like humidity.
Does a towel, specifically, matter in some way? If not, I'd rather use disposable materials than add a towel to the laundry every time I bake.