This is because the majority of Spanish speaking countries are located in the Americas, including:
* Latin America: Mexico, Central America, South America (except Brazil)
* The Caribbean: Cuba, Dominican Republic, Puerto Rico, etc.
* Spain: Located in Europe, but still a part of the Western Hemisphere
While some Spanish speaking communities exist in other parts of the world, such as the United States, Equatorial Guinea, and the Philippines, the vast majority reside in the Western Hemisphere.