I love getting serious responses to clearly marked sarcastic posts.
However, I don't assume anything of the sort, but the machine that does the build is obviously set to use a korean timezone (based on the kernel build timestamp of them - KST is "Korean Standard Time" [UTC+9])
As well, being that you seem to want to discuss build times and locations, Korea is nearly on the "other side of the world" from me (+13 hours from me (I'm -4, they are +9)), and the leaks usually occur during what would be normal working hours for Korea. The only exception I've seen (when I was paying attention), was the one time that I waited until about 6am my time to apply an update. That time, there was a leak that had a kernel build time of around 1900 KST. (I am making a reasonable assumption about their normal working hours here based on the fact that my company outsources some QC work to S. Korea.)
How I imagine its working is they are built in various locations on a server that is in Korea (hence the time stamp), this server is probably accessible by Samsung offices around the world (not to dissimilar to the CM build-box).
I might be completely wide of the Mark but I think a lot of the rom developing for the S3 has been done in Europe.