Folks, keep in mind that there is an option in the program that defines where coverart is stored: in the file tags, not in the file tags, in a folder.jpg file in the folder with the audio files, etc.
I personally have mine set to the folder.jpg option.
Right now I'm in a hotel 2400 miles from home.
If I was to 'get art from internet', or 'paste coverart' right now, how in the heck would you expect MC to get that new folder.jpg file onto my harddrive 2400 miles away, over the internet, when there's no direct access to the folder that the jpg would need to be added to?
I agree that a feature that doesn't work should probably be grayed out to indicate this is the case.
I think developers are treating this as a work in progress that will eventually function, rather than spending time disabling things, only to have to reverse that code later when the feature enhancement gets added.