Yeah, I have the same problem. I'd say probably because we feel like we've wasted half the day. Also something that happens to me is that the rest of the world is up and kicking at 8 or 9, when they start making noise. Whether its some guy mowing his lawn or my mom walking in the room directly above mine, I'm sleeping a lot less deeply. I might not actually wake up to every noise, but I'm a lot more awake. So yeah, that's my explanation for it.