Okay then, I looked at this and I see your misunderstanding. I'll admit, it is a little confusing.
The way the book is laid out, each chapter presents a "Problem-Design-Solution". What you're asking about is discussed in the "Design" part of Chapter 2. Often, in the "Design" sections of these chapters, various alternate methods of attacking the "Problem" are discussed in a general or theoretical manner.
In Chapter 2, Marco discusses various caching scenarios, and the one in particular he's talking about here is table-level SQL Dependencies. However, he is talking about how one might implement table-level dependencies in general, and shows how it would be done against a "Customers" table in some hypothetical application.
The thing is, this is NOT the caching method that ends up being implemented in the "Solution" part. That means a lot of this side discussion of caching scenarios ends up not being directly applicable to TheBeerHouse at all. Again, here Marco is only saying, "here are the things I looked at implementing, and here's why I decided to go in this direction instead of that one."
Bottom line: the Design parts do a good job of considering different ways of "skinning the cat" so to speak, but the actual implementation is presented in the Solution parts. If you are following along, you need to be aware of this.
Hope this helps.