Update: Apparently, this is as a result of change of policy by the South Korean government. They had previously made it mandatory for all games to be rated by the local Game Rating Board before they could be offered in the country. This forced both Google and Apple to remove the games from their local app stores. Apple recently added games back to their App Store. And Google is just following them with the Android Market.
Google has announced that they are now offering mobile games through Android Market in the South Korean market.
Apparently, the games were not offered in Korea until now because of some legal reasons.
Android developers revealed in a blog posting:
Starting right away, Android users in Korea can explore the many thousands of popular game titles available in Android Market and download them onto their devices. For paid games, purchasing is fast and convenient through direct carrier billing, which lets users in Korea easily charge their purchases to their monthly mobile operator bills.
They suggest game developers to start offering localized versions of their games for the Korean audience.