That’s perfectly rational, and I don’t mind at all as long as she stays still and lets me sleep. Which she often does.
When she doesn’t, things can turn weird. Several times I’ve awoken to somebody under my chin, enthusiastically licking or maybe chewing my beard. If I let that stand for even a few seconds she starts wanting to knead. Complete with claws, of course. And she gets positively manic about it.
We’ve had some strenuous disagreements over whether that’s proper behavior. Quite aside from the fact that it frickin’ tickles, I have dreams about waking up with half my beard gone.