Shooting (hunting) in the US and UK are totally different experiences. In the UK, most game shooting is done on private land by small parties of shooters who are known to each other and the landowner. Shooting is often a structured event with shooters placed, moved and supervised by gamekeepers.
In the US most hunting is done on public land; many millions of acres of game cover are free and open to anyone who buys a license. The number of hunters moving at random through federal, state and county forest lands is quite high (in Minnesota alone, about 300,000 deer hunters are in the woods this week). The use of blaze orange is a legal requirement in many cases, and firearm safety courses are mandated in most states. But when one is likely to encounter armed strangers in unexpected places, wearing blaze orange is always a good idea.
So the difference in shooting garb has more to do with the different environments than with culture. In the free and open American field, hunters have to be more concerned with seeing - and being seen - than with upland fashion statements.
