Easily ground your shoe: For dry climates, drill small holes in the sole- For wet climates, simply puncture holes, to avoid excessive wetting. The foot perspires and the resulting moisture provides a grounding path, to the ground you walk on. Slightly moistened surfaces of the shoe sole including these holes provide a slight bit of electrical conductivity. I think this a great solution for a rural or any unpolluted surroundings.
I reason that the amount of conductivity is likely greater than the dry land which is walked on. Inserted copper or metal conductors, as some manufacturers now do, is over doing it, in terms of electrical conductivity. Furthermore, as a shoe wears, a piece of metal will be noticeable and feel uneven or bothersome.
I have been testing this for months in a wet area (2013 Maine, USA). Water actually does not dampen my feet, even on some levels of rainy-wet lawn grass. Only in a significant puddle,or upon very soggy grass, does a little water penetrate. Perhaps this will be too much re-wilding for the ultra urban and suburban types. Added ventilation at the sole is an additional benefit. The ventilated moisture through these holes connects the sole with the earth. I think this is healthy for the soul.
The drilled hole method allows any existing shoe to be modified. So would the puncturing method. I first tested this with my work shoes and increasingly dilled more of my footwear. To ease drilling, a scrap piece of wood can be temporarily be put in the shoe, to avoid drilling too far. Or to avoid puncturing to far, beyond the sole. In any case, just a little caulking or gelled sealer can largely plug unwanted holes.