I asked the same question on another outdoor website forum (more for walkers and backpackers) and got a load of questions as to why I would need a knife. One recommended this forum and also gave some good advice. A lot made some unhelpful comments and seemed to imply that you shouldn't need a fixed blade knife in this country, "maybe Alaska or somewhere like that, but not in this country" was on such comment. What is you opinion to that? I explained that I prefer the security of a fixed blade and that not everyone just uses a knife when camping. Although I doubt it will be a regular use, but it will get used.
From my experience, walkers and backpackers tend to be more into using modern gear, and a lot of the time this can negate the need for a knife. Bushcraft, IMO, tends to be more about living off the land, foraging, gathering and preparing things for a fire and so on, and a knife is useful, if not necessary, for all of these. Plus, maybe you'll want to carve something, or the like. A knife is unnecessary for camping, really, but footballs are unnecessary, tv is unnecessary and so on. Just 'cause you don't strictly need it doesn't mean that you don't want to do some things that require it. That's my take on it, anyway . . .