Apachez, I couldn't agree more. I've switched off sleep in Kubuntu. That's a temporary workaround. I too find the official response you see above very disappointing.
The NUC is sold without an operating system because Intel intended for use cases beyond light office work on MS Windows. In particular supporting legacy boot is an obvious nod to alternative operating systems like linux. Lots of people are excited about the NUC for XBMC/Kodi/Openelec/Plex style HTPCs and the form factor was clearly inspired by the Mac mini which was commonly used as a light server / HTPC. Apachez, nice catch with that reference to OpenElec in BIOS release notes. Ha!
Intel - I'm still waiting for some action on this problem.