Buttons are at the core of any interactive app. But the options in terms of controlling their looks - especially when it comes to the text in them - are awfully limited. Thankfully we have icons, but some Markdown support or at least some option to control font size or making the text bold, would be very welcome.
Similarly, the Scanner object is effectively a Button-looking component with a fun consequence when you press it. As such, it would be very nice to have the same options as buttons.
And generally, it's all about making sure that components that share a commonality of appearance have a commonality of options to adjust said appearance, so that our apps look more uniform and that if we need a big button for a touch screen, the text in it isn't a tiny few pixels in the middle of the beast but something you can read easily despite unknown lighting conditions and longer distance from the screen.
Hope that helps a bit!