Since lower voltage means proportionally higher current for a given power, and higher current means more impedance, presumably having a lower voltage at the outlet means transmission power losses are greater than if a used a higher voltage.
How much more energy is lost per year due to the USA using 110V than if it used Europe's 220V? What is the dollar cost?
Assume the USA consumes 5 billion MWh per year, and 1 MWh costs $US0.20 to produce so total current (no pun intended) cost is $US1B p.a.