Years ago I did a comparison of how Word uses screen real estate compated to Pages (their feature sets are remarkably similar). Pages simply wastes fat less screen real estate that Word does giving you more room to see your actual document, and this is a recurring issue with Microsoft's UI design. The contrast is particularly marked with the iPad, where you get more pixels for your document on the iPad's 10" screen than in Microsoft Word on a 15" laptop screen.
Just look at the ribbon, toolbar, status bar, etc. Not only does this waste screen real estate, it wastes vertical space which is at a premium on widescreen displays. On a widescreen monitor, Pages minimizes this cruft or puts it in palettes and sidebars.
The show-the-content-and-hide-the-chrome trend in UI design isn't as presumptively valid as a lot of people try to make it out to be.
When you've got a document loaded up in a word processor, you're not just trying to read static content; you're working on that content, and the application you're using is a tool for editing and manipulating it. Hiding the chrome in order to show more of the document emphasises the document content as it is in the immediate instant, rather than the potential things you can do with that content, and makes it harder to locate the tools and functions for manipulating the document.
Minimal chrome might make sense in a web browser or PDF reader (at least to the extent that there's a smaller set of functionality necessary for reading documents, but hiding searching/bookmarking/referencing tools is just as bad) but in a word processor, it's much more necessary to have the application's own functional interface exposed.
But the funny thing about Word is it wastes screen real estate without exposing more functionality. Pages simply does a better job with screen real estate; Microsoft squanders it.
Just look at the ribbon, toolbar, status bar, etc. Not only does this waste screen real estate, it wastes vertical space which is at a premium on widescreen displays. On a widescreen monitor, Pages minimizes this cruft or puts it in palettes and sidebars.