The health benefits of "Earthing" come from the RF and Emmision test engineers, not having all that noise to mess up things for them saves there hair from being torn out, there stress levels from rising, and foreheads impact damage when the tests come back as failed.
The other benefits of "Earthing" come from the massive health benefits of not being electrocuted to buggery when you think you can unlodge that bit of toast in the toaster while forgetting to unplug it.