Are publishers hiding something?

Standing in bookstore, have you ever wondered whether the book is first, second or n-th part of series?

I noticed the same trend in my country. I suspect publishers to hide deliberately the fact that a book belongs to series. They probably (correctly) believe that people would never buy the second installment of series when they had not read the first one.

Even in blurb, they are omitting this info. On the other hand, modern series are often written in a way, which doesn't require readers to know previous development.

As I can feel some sympathy for poor publishers, I still feel scammed being a reader. The situation needs amendment. The easiest one would be pretending there is no series, just book belonging to the world of BLANK.

What do you think?