I was flying in PE on QF2 last year. I had enjoyed the Botrytis Semillon after dinner a bit too much and decided to go for a wander. I was pretty tired and wanted to stretch out. I found a row with 2 empty seats in J, rare on this route, and put one out flat and slept a few hours. I woke around 5 hours later, returned to my seat having not used any J services other than the bed and the FAs were none the wiser as they had been in the rear of the cabin talking the whole time. Was it brazen? Yes. Do I feel guilty? No.