From my observation of others and personal experience I've found the bulkier and heavier the knife the less likely you are to carry it and have it with you when you need it. Most of the large knives I have bought tend to stay in the drawer. Most of the guys I grew up with who bought Rambo sized knives humped them around for a few days, got tired of them, and then they were never seen again.

Sad to see a guy spend hundreds of dollars buying a dream in the form of a huge knife and to see it go unused because they got caught up in the symbolism of the item and overlooked the lack of utility.

Then again most North Americans will never be more than twenty miles as the crow flies from civilization. Even when hiking and climbing. Pretty hard to find a spot in the lower forty-eight that isn't twenty miles from a habitation of some sort.

Most of us in North America live near cities in a suburban environments. Even overlooking the annoying extra weight and bulk strapping on your 14" long orc sticker and walking around the mall is going to get you looks. At the very least people are going to think your a trifle odd.

It has to be noted, as hikermor did, that even in the woods most experienced hikers and campers eschew large knives if they don't have a specific use on that trip. You might see a machete on someone doing trail maintenance and the odd woodsy group feed my tote in a large chef fillet knife to prep the grub but generally if you see a large knife, particularly a large military style knife, it is a mark of inexperience.

North America has some dangerous wild animals. Cougars, several flavors of bears, alligators, wild hogs, even the normally docile buck can ruin your day.

I saw a couple of hunters run out of the woods by a buck. Everyone laughed and the buck got away. One of the guys spend most of the evening searching for the rifle he dropped. Hint: Either buy your firearms in colors you can see if you drop it, or don't drop it.

Given the number of potentially dangerous animals I have never met anyone who carried a knife seriously thinking they might fight them off. Fight off a grizzly bear with anything smaller than a Scottish claymore and I want to shake your hand. And other than what we saw Tarzan do in the movies I doubt any knife small enough to carry in one hand would help you much against an alligator.

Riding horses around the pampas sniffing out maneating pumas and wild hogs you carry what you please. Realistically if I found myself potentially dangerous area I would seriously consider taking my little knife and sharpening a pole. A spear is the traditional non-ranged weapon used by hunters of dangerous animals.