Pure Analog Pedals

Sometimes, instead of using electronics for processing audio we'll use air. Many different buildings are designed with their acoustic properties in mind. I've heard that high end studios sometimes have adjacent rooms meant solely for generating reverb. You can submit files online to the Tank or Silophone for natural processing.

Why don't we make guitar pedals like this? Obviously a small box won't have much reverb, but we could produce distortion. For example: a small speaker, absurdly overdriven, and a small mic picking it up.