Like most folks, the time I'm most likely to kill an exceptional buck is during the rut. When I go on those hunts on WMA's where I'm in the woods all day for days in a row, I need some creature comforts.
Sounds silly, but my shoulder harness pack is a piece of equipment I won't go without. I can take all the food, drink, and clothing needed for those all day ground hunts that I do. That pack enables me to tough it out.
When I was a lot younger and only threw what I needed in the pockets of my cargo pants, I'd not be able to stay nearly as long. I won't do those type hunts anymore without that type pack.