Because we want them to have a level of understanding of those fields, even if it's shallow. It's good for society if as many people as possible understand alg

Because we want them to have a level of understanding of those fields, even if it's shallow. It's good for society if as many people as possible understand algebra or World War I or how to read and write at a high level. If for no other reason than that as a democracy, we need our citizenry to have a certain base level of knowledge of how the world works.