About his hat: forgive me for being smart ass. That high crown was designed to keep the head cooler with air, and the brim was designed wide to keep the sun and the rain off the neck. Rolling it in certain ways would cause the rain to run off outside, not right down a person's neck. The brim was also useful for shade. All of these are important when you are riding for days in Nevada country gathering cattle.
Bo's hat is strictkly a cosmetic stage contraption. I think he took it from Little Jimmy Dickens, who needed a tall hat indeed. No self respecting cattleman would roll a hat that way.
