The US's relative freedom regarding private ownership of weapons means its just another part of some people's lives, where as in other, more restrictive countries, its not. It could also be media-related. I have more knowledge of weapons because of shows on the History Channel...and I took a military history class in high school.
May not be the best example, but imagine going to Africa and trying to talk to a tribesman about the Internet. They'd have no more clue about it than if they tried to tell you about bringing down a Wildebeest with a spear or bow-and-arrow.