In a flying game, you are able to keep the hats that you wear in the rest of the game on. However, some hats are very big or get in the way, like the Butterbrew Barrel or even the wizard hats. This gives the player wearing the hat an unfair advantage as everyone else finds it harder to see past them. If hats were disabled in flying, this would be fairer.
I could probably also suggest that because some store-bought hats give an advantage to players in-game, it could be seen as violating the eula, but I'm not sure I should go that far.
I could probably also suggest that because some store-bought hats give an advantage to players in-game, it could be seen as violating the eula, but I'm not sure I should go that far.