Wow I hate the way WoTC (and other companies) present some elements of their adventures.
Some background: my group wanted to try high-level 5e play and so I offered to run them through one of the deeper levels of Waterdeep: Dungeon of the Mad Mage. Because it wasn't part of a normal campaign, and the chaps were creating new characters, I decided to run the adventure exactly as written.
The most irritating things about the adventure was the almost total lack of stat blocks. The adventure instead directed me to the various stat blocks in the Monster Manual or in the adventure's appendix. That's fine as far as it goes, until the characters have an encounter with four kinds of opponent. One of the foes in that battle also had a special suite of spells not listed with the main stat block. How handy. During the battle, I was flipping backwards and forwards through the two books like a wild man trying to keep track of hits points, armour class, spells, abilities and more.
True, I could have spent more of my precious time preparing, but why should I? Why does a publisher assume I've got loads of time to find and copy various stat blocks from various books? I would, of course, print the stat blocks from legally purchased PDFs–if WoTC made them available.
It doesn't seem to me WoTC have worked hard to help the GM actually run the adventure. In an ideal world, I should be able to pick up the adventure, read it and run it. The lack of comprehensive, organised and collated stat blocks makes the process of getting ready for the game so much harder, longer and more boring.
The publisher in me understands this:
More stat blocks = increase page count = increased cost = reduced sales.
That said, as a GM I don't care.
Fewer stat blocks = more friction = extra prep time = increased frustration.
When I buy a module, I want it to include everything I need to run the adventure. I don't want to spend hours and hours doing prep work that should have been done for me. (It wastes my time–something of which I have a finite supply, and something I value much more highly than a couple of extra dollars).
One of the most critical parts of a publisher's job is to understand not only who is buying their books, but also HOW they WANT to use the books. A publisher should reduce the friction a GM faces when using their product. Make a GM's life easier and smoother, and they'll likely buy from you again. Don't and they won't.