And that just proves my point. You switch off an iPad by closing the cover; it goes to sleep because you've closed the cover.
On Windows8 though, I would love to hear the rationale behind putting 'Shutdown' inside 'Settings'. Most stuff that people have lost in Windows8 can be found by just looking in that menu thingy on the right of the screen, but burying the 'Shutdown' inside a submenu there strikes me as a little bit odd.
On Windows 8 I just close the cover on my Surface, which I'm typing on now, or poke the power button when using my desktop. Simple.