Tastes change due to the penny press
"In effect, the lure of the popular market broke down the traditional hierarchy of taste that had been expressed in the physical form of the book," Starr, (p. 137), chapter 4 (The Creation of the Media).
Book prices were kept low due to the competition between the cheaper formats. During the 1850's the price of cloth books were $.50 with smaller volumes costing half of that. Literature was being published in a variety of editions for different type of readers. In the past, high culture was linked to an elite section of the public who could afford expensively produced books. Because of the increasing diversity in readership and affordability, the general public was becoming more of the reading public. Culture and taste were progressing from the elite to the common.