B&N is probably more akin to WH Smith, in the UK. Originally, it was a single store, in New York, that grew out of the merger of two bookstores, owned by a Barnes and a Noble. it was a fixture of Manhattan. Current owner and CEO, Len Riggio, started out dealing in textbooks and remaindered books. He expanded operations and eventually bought the B Dalton chain of shopping mall bookstores, as well as Brentanos, a Northeastern chain of stores. He thenacquired the Barnes & Noble store. He bought a chain of superstores, known as Bookstop and Bookstar, which operated in the Southern and Southwestern US. He took the Bookstop concept of large retail bookstores and mixed in the old world charm of the Barnes & Noble Store and rebranded Bookstop stores, then expanded with new Barnes & Noble stores, through the 90s. The company became the nation's leading book retailer. Borders was a chain affiliated with Waldenbooks, which was a mall rival of B Dalton. As the superstore concept caught on, both Waldenbooks and B Dalton began to be shuttered. With the rise of Amazon and on-line retailing, both chains faced declining sales. Borders focused on a youth market and put a lot of capital into music and video sales; but, the growth of digital music and video cut that market. They jumped in headfirst into the manga boom and filled their stores with product. What they didn't do was develop on-line retailing and they were heavily financed with debt. This eventually drove them out of business.

Books-A-Million was a much smaller chain, that was a distant third in the marketplace (well, 4th, if you count Amazon), who specialized more in remaindered books. When Borders went under, they inherited a bit of their marketshare; but, the actual market shrank, as publishers lost a major buyer. The overall US book market shrank.

It's a bit disingenuous to say B&N's market woes are karma, as they never deliberately targeted smaller bookstores. What hurt smaller operations was the skyrocketing retail rental prices, which jumped massively in the 90s. It became increasingly difficult to run a smaller operation at a level that could pay the rents the landlords demanded. I worked for B&N for 20 years. We actively steered customers to rival bookstores, if they had the product in stock, if the customer was reluctant to order or needed it more rapidly. Yes, they did take business away from smaller bookstores, via volume and price breaks on some things; but, the average price of a book was the same at B&N as in smaller stores. the big discount was on bestsellers, though hardcovers used to be at least 10% off. That went away and was replaced by the member program, which gave a blanket 10% off or an additional 10% off already discounted books. However, B&N and Borders did not actively under-price books to drive away competition, as Amazon has.

Amazon started out with used and remaindered material and moved more into retail books after going public, with that kind of capitalization. However, they have demonstrated, consistently, that they are no friend to publishers and authors. they have tried to dictate pricing to publishers, who called their bluff. A few years ago they delisted all of Macmillan's titles, and did the same with another publisher (I can't recall which one; but, it was one of the top 10). They have tried to undercut authors on ownership of their copyrights and their publishing program is a bit draconian,especially in relation to Kindle. B&N, for all of its many faults, worked to support authors and publishers, to everyone's benefit.

B&N moved into toys and collectibles and expanded their gift departments, to compensate for shrinking book sales. It's not just the competition from Amazon; US publishing took a massive hit when Borders went under and never recovered. fewer titles are being published and less backlist is being kept in print. Digital has expanded and quite a bit of out of print material has been reissued; but far less of contemporary authors. Authors are earning less and contracts are even more one sided than they traditionally had been. Comics has been the same, if not worse, as creative talent struggle to earn a living from page rates, with royalties almost non-existent (especially compared to when the royalty systems were introduced).

B&N, a few years ago, went heavier into comics for the newsstand, as they were the nation's leading newsstand retailer. However, anecdotally, it wasn't much of a hit. Magazines, in general, are way down and comics mostly sat there. B&N only dealt in returnable product, which cut out a lot of material, though they were better stocked with trades.

Brick & mortar retailing is expensive, under any financial structure and Wall Street demands massive return on their investments and immediate return. They care about next quarter, not the next 5 or 10 years. That is what is killing retail stores. Companies cut their costs to the bone to get higher returns, which destroys service and quality, which loses customers. It becomes self-fulfilling.