The construction of audience feedback as a form of "fan mail" was the most obvious example of the early commodification of audience feedback. To a certain extent, audience feedback had always included occasional expressions of flattery and support toward news publications. Concurrent with increasing professional discussion about how to manage audience feedback was the scholarly study of feedback forums, especially a number of early studies that tried to discern the demographics of successful LTE writers. While the feedback forums of mainstream media became less accessible to all but the educated middle class, advances in printing technology in the mid-20th century allowed for a dramatic expansion of alternative newspapers and niche magazines, many of which were far more accommodating of submissions from their communities. The slow, steady movement of mainstream newspapers toward making audience feedback forums more favorable toward cultural elites corresponds with editors' efforts to justify their increasingly obstructionist approach to providing public forums in their pages.