There is an element of truth to "hiding" content. There is a seller "tension" between really defining valid concrete categories, such as books, and using vague ambiguous interpretations of the word "books". On one hand, Amazon wants the customer to easily find a product, yet on the other hand they want to throw as many products at the customer as possible hoping that it will either spark their interest in that irrelevant product or that the customer will simply make a mistake and unintentionally buy that product.
When looking at the movies available on Amazon, they are not exactly upfront about identifying which movies are available for free as a member of Amazon Prime or which movies you have to pay for. And along those lines, Rotten Tomatoes, identifies movies that are now available on Amazon. Sounds good, but it seems all those movies you have to pay for. Clearly, Rotten Tomatoes could, if they wanted to, could identify which movies are "free" and which aren't.
Continuing with my rant, on a larger scale. The capability to instantly manufacture (fake) webpages is absolutely astounding. Recently, we had to buy a new clothes washer. I thought that I went to the webpage for our local Lowes Home Improvement store. As I was looking at the webpage, it just didn't seem quite right. After a while, I realized that it was not the real stores website.
A while back I was trying to find some batteries by providing an actual product number. A lot of hits were generated, but then I went to check out the availability of the batteries for purchase, they did not actually have them.
In another case, can't remember the product. I had a variety of tabs open. On one site the product was listed at $x. On another tab after following several links, I arrived at the same product. This time the price was $x + y. So depending on how you arrive at a particular webpage, the price of the product can change. This is very scary.