I think that is unfair to other players. That would create a one-sided game.
It's like having a weapon while the other is bare-handed. That would look so weak.
As you can see, this is not like other games like mmorpg. Though we can level-up our tori but it doesn't gain anything except for the belts/qi which you can use to buy qi restricted items. But those items didn't add some "powers" over your tori. Who is gaining is the player itself which is the experience in game
I like having weapons in game though. But I dont like a one sided game.