This is a case where you should not judge a book by its cover.
Not only does this book have well-explained theory, it also has lots of examples and includes many fuzzy "versions" of common mathematical concepts, not just "sets" as we tend to think of them.
Importantly, there is a lot devoted to making sure the reader understands what is going on... which is important given this kind of topic. The preface contains a lot of important philosophical preamble.
One of the best books on fuzzy theory I have ever picked up.