How is a fixed blade knife more dangerous than an SAK, particularly one that doesn't lock?

I do carry an SAK Farmer as my main tool and it works great and sometimes a small fixed blade depending on my activities but really don't see the need for anything longer than a 4" blade even when hunting. I know a lot of the guys that are really into knives don't feel good without three or four different blades on them for a day hike but just like backpackers have their interests, that is their "thing" and I don't begrudge them their fun.