More-so than anything else, Korea is a country obsessed with festivals. You'll find them for most anything - ranging from religious inspired festivals such as Seoul's Lantern Festival (for Buddha's Birthday) to debaucherous borderline orgies such as Boryeong's (in)famous Mud Festival.
While it's true that a lot of the Korean social experience seems to revolve around consuming vast quantities of alcohol and making out with your peers, there's also a lot of opportunities to get out and interact with people without the influence of alcohol. A year round calendar of festivals means that, if you're game, you'll rarely have a weekend where you won't have the option to get out of town and soak up a little bit of the local culture.