For my pixel art book with No Starch, they insisted on Word templates and it worked out well for a couple of reasons. The first being because their editing team was so used to using the template for feedback. It was easier for me to adapt to the publisher than the other way around, and the whole process was smoother and quicker.
The second reason was to do with a change in format as the book was nearing completion. It's aimed at kids (8+) and adults, but we decided having an open and lay flat printed edition made the most sense because it makes following the tutorials easier. This resulted in the layout needing to be tweaked for a couple of hundred pages, which the publisher handled because we used their template system.
So while it may be annoying for a writer to have to change their methods, it can save you a hell of a lot of work because things change unexpectedly (and in my case for the better).
The second reason was to do with a change in format as the book was nearing completion. It's aimed at kids (8+) and adults, but we decided having an open and lay flat printed edition made the most sense because it makes following the tutorials easier. This resulted in the layout needing to be tweaked for a couple of hundred pages, which the publisher handled because we used their template system.
So while it may be annoying for a writer to have to change their methods, it can save you a hell of a lot of work because things change unexpectedly (and in my case for the better).