Besides, just because it's "available" doesn't mean it'll actually work. I recently had four consecutive flights (738, 739, 753) Y/F where it didn't work in my seat, and I'm talking about a tablet which has much lower draw than a PC. Last flight on a 739 (not one of the four) captain announced that there was no in-seat power for the entire a/c.

I don't assume anymore that I'll have power at the seat.