There are single receptacles capable of both 120 and 240V. They're called NEMA 14. NEMA 14-20 technically exists, which would give you multi use 120V or 240V 20 amp outlets. The problem is nobody uses them, as this is non-standard and nothing uses the plug besides industrial stuff.
Unless there's a truly useful application, I doubt it'll see wide use in US. Sure, 240V is nice, but there just isn't that magic thing missing from 1800W appliances today. Being able to boil water a little bit faster is not worth rewiring every house and changing standards around the country.
Unless there's a truly useful application, I doubt it'll see wide use in US. Sure, 240V is nice, but there just isn't that magic thing missing from 1800W appliances today. Being able to boil water a little bit faster is not worth rewiring every house and changing standards around the country.