I was shocked to find it's a faux pas to rub disposable chopsticks to remove potential splinters. I was taught this is what you're supposed to do with disposable chopsticks.
Do I just use chopsticks that will put splinters in my mouth just to not appear rude?
But everyone I met who does splinter cleanup does it _every time_ even without a cursory inspection. So the metaphor is… maybe more apt that you are cleaning a plate despite not seeing whether it’s clean or not first
I always rub mine together, but I suppose it would be interesting to know if you didn't, how often would something bad happen? Is it more likely to hurt your mouth or your fingers?
But you move away from break apart disposable chopsticks in Japan long before you get to high etiquette dining. In my experience, basically every restaurant in Japan that isn't of, like, fast food tier, provides actual chopsticks instead of disposable ones.