So why aren’t buttered sandwiches popular in the US? It is easy to understand why Marmite might not make the leap across the Atlantic, but butter is surely a staple. The explanation, I think, is that, like their
horrible chocolate, a lot of American butter is substandard, because of looser regulations; European butter has to have
a higher butterfat percentage than American butter and those extra percentages add a lot of flavour. American butter is usually designed for cooking and, unless you go out of your way to look for the good stuff, it doesn’t add much to a sandwich.