Do Readers of Shapeshifter Romance Read Only Shapeshifter Romance?...Amazon Says So

I have a perfectly functional Barnes & Noble Bookstore about 10 minutes from my house, not to mention, several struggling used bookstores, but like a lot of Americans—good or bad—I tend to buy more and more of my books online. Convenience has begun to supplant the feel of a physical book in my hand when making buying decisions. Of the 11 books I bought last month, all were purchased online, including a handful of Kindle books.

One thing about Amazon's sales pages I always glance at is the section, "Customers Who Bought This Item Also Bought." This feature supposedly connects you with fellow readers by providing book recommendations from strangers. I'll admit I've purchased several books based on this clever bit of virtual "hand-selling" in the past.

While visiting the page for my book, Wolf's Den this morning, however, I discovered something curious in the 25-page slide show of books readers "also" bought. All were shapeshifter romances.

Is Amazon telling me that romance readers are so regimented that they never stray outside the lines of the shapeshifter subgenre? Pretty hard to believe none of Wolf's Den's readers have ever purchased a romantic suspense novel, a cookbook, or even some classic literature.

What gives Amazon? Did readers really purchase those 100 other wolf/big cat books and nothing else? Or was that just a random list generated for me based on a set of keywords?