The industry term is "affidavit returns." Paperbacks and comic books both evolved from the magazine format and were distributed by magazine distributors. Comics grew out of a combination of pulp magazines and newspaper comic strips and their size was borrowed mostly from the pulps. The pulps were already close to what paperbacks became and the paperback business took over much of the genre fiction that had emerged with th pulps (mystery, western, romance, sci-fi, fantasy, etc...). Magazines were sold to newsstands on the affidavit system. When the time was up on an issue, you stripped the covers off and returned those to the distributor for credit on future orders. The stripped cover was proof you had destroyed the magazine, rather than sold it. it's why you would see notices in paperback books about if you had bought it without a cover). It was less likely to sell without a cover, and publishers didn't want unsold copies back. it kept retailers from being stuck with things and reluctant to take on new product, while also preventing them from gaming the system, easily. It worked fairly well fro some time.

Hardback books were different; but, hardbacks were reserved for "literature" and more important reference books. Paperbacks were the lesser offspring, fr the unwashed and barely literate masses, though they also became a better conduit for access to great literature, at an affordable price.

We used to think stripping covers was a pain, both for magazines and books; but, it worked fairly welland did let smaller booksellers be able to operate.

That blog is missing a major element of bookselling in the 90s. Retail rental rates skyrocketed, due to the booming economy and mom and pop book shops, who worked on tighter margins, were squeezed out. It affected both retail and used vendors heavily. Part of the reason for the decline in the wholesalers, aside from technological changes, was a decline in clients. Chains like B&N and Borders developed their own, more efficient distribution systems. 1996/7 also saw a big shakeup in the publishing game, as that Holiday season (I think it was 96, going into 97; but, might have been 97/98) saw a massive wave of over-ordered titles and a ton of returns to the publishers. Several publishers had their cash flows severely damaged and were in financial trouble. This led to a revamping of the ordering models, with lower initial orders and faster re-orders and reprinting. before that, publishers would make far larger initial printings and encourage larger up-from orders, rather than put out a more reasonable print run and see how it does with more vigorous marketing.

The other factor is the rise of e-commerce, which changed everything about brick-and-mortar retailing. In the mid-90s, Amazon was a platform for selling used books. Once it went public, it grew to dominate the industry, creating new ordering models. Borders financial woes also started in the mid-late 90s, which affected book ordering. Lot more forces at plat than that blog suggests. Also, that "Airport Model" had been in play for a long time. One of the most dominant actors in determining sales for the NYT Bestseller list was sales at O'Hare Airport, as the busiest airport in the country. if a book was selling well there, it went on the list, even if it was a turkey in large chunks of the country. Vendor-served paperback racks are as old as paperback books. The main difference is that they went from being mostly genre fiction to bestseller racks, though that started in the late 70s. Like many industries, the commerce-driven 80s changed a lot of things, as mergers were greenlit by a pro-business conservative government, both in the US and Europe. Mass mergers led to fewer competitors and more homogenized products, which, for publishing, came to a head in the 90s. In fact, much of the 90s and 00s is the fallout of the Reagan & Thatcher years, as well as similar government/industry relationships in other countries.