It's Home & Student, and a lot of students use it at home, as distinct from in the classroom. Also, it's not just WP. Plenty of people do stuff that benefits from using Office. They have hobbies or are members of local groups that produce fliers or newsletters (church, youth, etc).

By the way, Windows includes a free word processor, WordPad, that does what most home users need without them having to buy Office. There are also free viewers for Office docs...