So thats what you call them in Canada here in the deep south some of us cal them ( Sock Hats ) though I have heard them called toboggans, which in some places toboggan is a form of sledding isn't it! that one bubbles is wearing is called a Bobble-hat, Or in this case a " Bubble-Hat"
Lots of hats....wear one everyday. Ball caps...felt hats.....wool hats....cowboy hats....got em all. Also have a very old neighbor with so many wrinkles on his head.....he literally screws his hats on.....htgt!