Final answer:
The late 1990s saw a shift in the consignment system for distributing doujin due to the emergence of online retailers like Amazon and changes in consumer culture. This, along with the decline of large bookstores and advancements in printing technology, allowed smaller consignment systems to play a more significant role in distribution.
Step-by-step explanation:
The shift in the consignment system for distributing doujin occurred in the late 1990s due to several factors that changed consumer behavior and market dynamics. The rise of online retail giants like Amazon disrupted the traditional retail space by offering a vast inventory of books and convenient online purchasing options. This transformed the way consumers shopped and markedly influenced the distribution of printed materials, including doujin. The advent of online shopping, coupled with the growth of consumer culture and advanced printing technologies, led to a wider reach and distribution of various publications, hence amplifying the importance of bookstore consignment systems for distributing doujinshi.
Additionally, the decline of large bookstore chains and the ubiquity of Internet access enabled smaller consignment stores to gain a stronger foothold in the industry. The necessity to adapt to a rapidly changing market environment, influenced by the digital revolution, contributed to the shift away from the previously secondary role of the bookstore consignment system in the late 1990s. This transformation was part of a broader change in patterns of acquisition and consumerism globally, as seen with the advent of department stores and alterations in traditional economic mores.