First, regarding electrophysiology in cephalopods, here's a pertinent quote from one of the papers I've read:
"To date, all electrophysiological recordings from cephalopod brains have been done either in brain slices (Williamson and Budelmann 1991) or isolated brain preparations (Mislin 1995; Laverack 1980), or in heavily restrained animals (Bullock and Uter 1976; Bullock 1984)."
The article goes on to describe a procedure wherein they first inserted electrodes into the animal's brain and then recorded activity as it was awake and behaving. There's still a ways to go, as far as I'm aware (I could be wrong); methods of recording, for one, are still not non-lethal eventually.
I'm not sure what kind of procedure would have to be done to get a reading of cuttlefish electric activity while they're asleep; sleep studies on humans are complicated enough. I don't know if we've done enough studies of cephalopod electrophysiology to study what happens in their brain when they're asleep.
I was only joking of course!
The issue of expenditure on "non-essential" scientific research is, however, political. And globally, too.
The amount of funding allowed on Cephalopod behavior is relative to the importance assigned to it by any collection of like-minded politicians (Or perhaps, indeed, their fear of a 'tabloid' media backlash).
Bearing in mind the neutral zeitgeist of this forum - I'm still happy to declare myself a proud Liberal.
And what we don't know now, about Octopuses (Or indeed any other animal) is something we might find beneficial to know - If the money was available for meaningful research!
You would not expect a right-wing politician to ever spend money on anything, voluntarily!
Yet voluntary expenditure is the only way forward, with respect to ALL Scientific Research (In this case, with particular respect to Cephalopod Biology.)
Indeed, though some might accuse you of being insufficiently cynical. :P
I have no idea what goes on in the NSF, but I know a little about how NIH funding goes (which would be most related to sleep research; from what I know of the NSF, they tell anyone who mentions 'health' in the medical sense in applications to send their application to the NIH), and what seems to be the trend is increase in funding of research that will more immediately translate into clinical benefits - translational research especially - and that means they're going to be funding studies on vertebrates, because their anatomy is most similar to humans.
As goes the money goes the science, unfortunately.
But we can get inventive in our grant-writing.