Welcome to the forum. Stop by the introductions area and let everyone know you're here.
Hunting or civilian weapons may or may not have the "shiny" finish as you call it. Some are all black, cammo, stainless, have a nice wood stock or maybe synthetic, depends on it's use. Synthetic stock doesn't swell or shrink with weather like wood, stainless won't rust, cammo can help you hide for the harder to hunt animals, they all have a reason.
Military does not want ANYTHING shiny, ANYWHERE. Why? It creates a glare from the sun, reflects light at night, basically gives away your position.