As there is virtually no drugs in South Korea or other east asian countries, addiction do have a different perception/connotation. Nonetheless, the word "addiction/중독" is used to refer smartphone addiction.
There is definitely alcohol being consumed in South Korea. Anecdotally, I've seen some hard-drinking South Koreans. In terms of real data, the country ranks pretty highly in overall drinking.
https://en.wikipedia.org/wiki/List_of_countries_by_alcohol_c...