Not only can you hide the buttons in the ribbon (which is nice if you typically use keyboard shortcuts), but the experience is consistent with other recent Microsoft applications. I'm not sure a computer novice or even 50% or more of non-power users would have any idea what the buttons on Finder do (does anyone know what that eye button does before they click on it?), and I think that's the target demographic here. Power users know how to hide unwanted buttons or the text that goes with the buttons.