Heck, half of the Asian weapons are wierd, and pretty specialized...
A lot of the Asian martial arts show the same features. Many of them - especially the Chinese - utterly fail on practical terms, which makes you wonder 'how did this evolve'? They had something in mind. It was pretty successful at one point. What happened?
One explanation I've heard is that many of the Asian martial arts evolved in highly specialized contexts. For example, "This martial arts fighting stance and forms are based on the assumption that the user is standing knee deep in a rice patty when the fight breaks out. Once you understand that context, it makes more sense." Or perhaps, "This martial art evolved with the assumption that the practitioner would most likely be standing on a 30 degree snow covered slope. Under those circumstances, it's very practical." Or perhaps, "This martial art evolved in the context of military practice, where you had a guy with a spear standing to either side of you, and the whole point was to help that guy deliver a killing blow and get your spear back before you got stabbed."
What tends to happen, not only recently with the post 1970's popularization of the martial arts but over time, is that the assumptions behind the system tend to be lost and even the masters tended to forget why they were doing things. One problem that tends to pervade Chinese thought is that they tended to discover things first, but then record the knowledge in form of analogies and mysticism. You get this in the west as well - trying reading a pre-Newton text on alchemy. The problem was over time people would forget what the analogy actually stood for, so you see a tendency in China for things to be highly advanced and evolved and then get lost in translation. When the West brought accurate water clocks to China, they were regarded as marvels. Problem is, the Chinese had actually invented them more than a 1000 years before and lost the technology.
I suspect they are more show and "just being different" than commonly used.
Well, stage craft itself had a highly refined martial art for its own 'just for show' purposes. I really like the movie 'King of Masks'. I can't help but be slightly political here, but probably one of the greatest tragedies in human history was Mao's attempt to destroy the culture of what had been for most of human history the most refined one on the planet. There is this huge break in history which we can only dimly look past now. So much humor, art, and knowledge just went poof along with the people that held it.