RE: coffee
I love my coffee, but avoid it when going deer hunting for several reasons. First and foremost it smells. It contaminates the air, your breath and let's not even mention the implications of spilling some on your hunting clothes or hunting area...
Secondly, it makes me have to urinate every 20 minutes or so.
An apple will give you a boost (sugar) and quench your thirst. Oh and obviously provide a 'cover' scent.