There are different tools which can be used, depending on the type of full text one is looking for, such as government documents, annual reports, merchandise catalogs, or even books. In addition to this, there is a growing amount of archival material that users would probably never even think to look for online, such as the archival material contained in the Library of Congress's American Memory project. Well, on the face of it, and looking at only one journal, it seems like a good idea. But, look at the ramifications.
Some publishers allow access from only certain workstations or certain buildings.
Some require that an ID and password be entered. Some offers are only for the feature articles, but not for the entire journal issue. And on it goes. Now multiply these issues and questions by the hundreds of journals offered by publishers. To adequately manage the growing electronic journal population, we had to establish a policy that made growth manageable.