Now I am the one confused by your question

the fact that you need a device does not change the question.
I'll rephrase to see if it helps. Why are all the popular LPF and HPF devices powered? One would think that you would not need power to remove frequencies since passive circuits like the tone knob or the Reverend bass cut do exactly that. Are there any passive options in the market?
I did a little bit of research and found two passive HPF circuits
here. I obviously don't understand much but it likely means that it's possible.