I think he was saying that option is not enough, that it should be automatic? That menu option is pretty standard in modern DSLRs, are there cameras without it?
I guess I am not following. The camera won't work (i.e.: no picture) if the setting is "do not release shutter without card".
"No card in camera" is displayed on the rear LCD screen in this setting. On the 5DIII, it also flashes "card" on the small LCD display by the shutter button *and* in the viewfinder display. The camera will *not* take a picture, no matter how hard the shutter button is depressed.
If the setting is "release shutter without card", then the camera functions no differently without the card in place. No warnings, nothing to tell you the card is missing.
Seems pretty automatic to me, if the correct setting is enabled.