Few people realize this, but mushrooms can move. They look like they're rooted in the ground, but in fact they simply have very stubby feet which they dig into the soil during daylight. At night time they creep along, like a penguin with more than two legs, tasting their way across the ground. Fairy rings are nothing more than a group of mushrooms who've all wound up at the same piece of savory dirt.
Don't believe me? I'll prove it to you.
Go outside and find a mushroom. Preferably one on a relatively comfortable stretch of ground. Come evening, lie down facing the mushroom. Don't move. If you can manage not to breathe either, all for the better. Stare at the mushroom, and don't blink.
In the morning, come and tell me whether or not the mushroom moved at all during the night.
(Told you so.)