In America, it depends what part of the country you are in, whether your largest meal of the day will be the mid-day meal of lunch (called dinner in some regions) or supper (the evening meal, also called dinner in some regions).
Even if you eat a small sandwich for lunch, it will be rare for it to have butter on it (unless it is fried, like grilled cheese). It will likely also have various spreads, sauces, or vegetables on it. A very basic/classic American sandwich has a slice or two of ham, slice of cheese, pickles, and mustard, for example, which is much more complex and flavorful than what this article talks about.
The only meal where Americans might commonly eat only bread and butter is breakfast, and then it very likely to be toasted.
Even if you eat a small sandwich for lunch, it will be rare for it to have butter on it (unless it is fried, like grilled cheese). It will likely also have various spreads, sauces, or vegetables on it. A very basic/classic American sandwich has a slice or two of ham, slice of cheese, pickles, and mustard, for example, which is much more complex and flavorful than what this article talks about.
The only meal where Americans might commonly eat only bread and butter is breakfast, and then it very likely to be toasted.