Depository libraries have traditionally enjoyed a pretty sweet deal—we receive free copies of documents in return for space, processing, and staff to help people use them. Depository libraries have served as key players in two areas of public policy: 1) public access to government information for the needs of today; and 2) widespread distribution of documents helps them survive to form a historical record.
Shaw, James T., "The Status and Future of Government Documents" (2009). Criss Library Faculty Proceedings & Presentations. 5.