Hello,Yes, they actually need very well rotted leaf humus or the dirt that live moss creates in their diet right?
They are very easy, thriving on normal, decaying leaves, mixed with a lot of calcium, with some moss, lichens and wood (not white rot).
They even have been observed feeding on supplemental foods. Basically they are ridiculously easy, the easiest pillipedes can get.
I actually don’t know a single pillipede which needs the soil mosses create, except maybe Glomeris balcanica, which apparently need moss to breed.
-That being said, it is always good to offer moss!