In the US, most residential power outlets never have a wall-switch controlling them whereas whenever I travel (say, on my frequent trips to India) every socket has a controlling switch. First question: Is this because of the relative danger differential of 110 V versus 240 V? Or other reasons? Is live insertion of plugs into sockets routine all over the 110 V nations? Second question: Some equipment seems to spark more / larger at the point and moment of insertion than others. What determines this? Eg. my cellphone charger never seems to spark on a live insertion but laptop chargers or my table lamp sparks livelier.