I also think it is a positive indication that you are supplying correct composting conditions, and that other fungi should thrive. I have sourced fresh ,coarse, wood chip this Summer for the paths, where it has spread onto the beds in particular, several very attractive toadstools have appeared, not qualified to determine whether they are a harvestable crop(One can only get it wrong once!! ) but they are quite pretty. Field mushrooms are also prolific in areas, these could be encouraged as a future project I think.