The first reason to wear any head cover is to protect your head from the weather. You might turn the baseball cap backwards if you're firing a scoped weapon from the prone position, or you just want to look like a dork and blend in with everybody else.
A boonie hat provides the best protection against the elements, and the best camouflage. The more mangled it is, the better it disguises your head and face. Psychologically, the human brain instinctively recognizes a human face before anything else, with hands second. That's why snipers will either wear face paint, or a sniper veil over a boonie hat.
Hands are delicate, and need protecting. Some of the gloves have padding and hard covers in areas of the hand. Look at a goalie's gloves for an extreme example. Some cop gloves also have several ounces of powdered lead sewn in over the knuckle area, to add to the persuasive power of a fine glove. The more knocks and scrapes your hands might take, the heavier the glove. A good glove also increases security of grip, so you don't drop your weapon, or let go of something.
A lot of shooters will have gloves with half fingers, so they still have fingertip dexterity. Snipers usually wear standard pilot's Nomex flight gloves. They are extremely thin, and provide a good sense of touch, something pilots need, too. Plus, any kind of glove provides some measure of camouflage for the hand. A gloved hand is not as instinctively recognized as a bare hand is.
Oh, and speaking of night vision, we finally saw Silence of the Lambs last night. It was pretty good; I just had to look away at the more gruesome parts. Anthony Hopkins was VEY creepy!
I didn't know that, about faces and hands being so recognizable!
So if I send my Finder on the prowl, he should have at least a hat, face paint, and gloves.
Can I get away with a Stetson? Maybe a straw one (it's May, after all)? The sunshine through the spaces between straws should create a dappling effect on the face that breaks up the features ...
Or mayhe he just uses a baseball cap when he's Hunting ...