Hey…that’s very interesting man!! Makes me think of the Amish who swear that demons can infest a home due to the electricity. Some claim that placing an electrical shell around your living area (think of how the home is wired) makes it easy to attract negative entities. Same goes for living under or adjacent to high voltage power lines. But your question as to the WHY that’s the Standard is a great one. Of course there’s a +- deviation so a home could be getting 432 volts at the main breaker etc etc(?)