I second the "its a pretty good day" comment, but I imagine there are thin breatheable beanies that work well, I know I see other riders sans hair using them in the summer, so they must work.
As a Canadian however, your toboggan statement was rather odd, never seen that word used for anything other than this.....so it made for a strange picture in my head after reading your sentence....
Grew up in the midwest and went to school in Mississippi. First winter down there everyone was calling it a toboggan. I actually pulled up a pick of a wooden sled like you did, pointed to it, and said thats a toboggan. Its really cool how identifying words change thru regional use.
At the same time, just because you wear a hat while on a toboggan, that shouldnt make the hat a toboggan any more than it would make the gloves you wear toboggans.
But hey, when in Rome, so i quickly accepted the local term.