From the admin side...
It would be helpful for design purposes.
Sometimes I'd like to have something on the left hand column on desktop, but I don't want mobile or tablet users to have to scroll through it before getting to the main content.
There's such a disparity in display between a wide screen desktop set up and a mobile device.
As an aside, I think the title for the block (that shows in the front end) shouldn't be required by default, not every bit of html needs a title.
