Mushroom hair

Today my wife and kids visited Panarottis at boardwalk Richard's Bay.. My wife ordered a chicken and mushroom pizza. Whilst eating she noticed that there was hair in the pizza. She informed the supervisor who told her it was mushroom hair. We have eaten mushrooms all our lives and have never experienced this hair that they spoke of. If this is indeed the truth about mushroom hair don't you think it should be mentioned in the menu that you will find traces of mushrooms hair in your pizza...