Seven airlines, including carrier Korean Air Lines Co. and its rival Asiana Airlines Inc., accommodated 15,983 people to 152 "flights to nowhere" since the service was introduced late last year.
The Korea Customs Service (KCS) said the flights were held between December 2020 and May 2021.
Air Busan Co. conducted the most number of such flights with 35, trailed by Jeju Air Co. with 34, and Jin Air with 33.
The KCS added that passengers availing of the flights had bought 22.8 billion won worth of duty-free products over the past six months.
Flights to nowhere, which would temporarily be operated until the end of this year, start and end at the same airport and offer tax-free sales.
Passengers are also exempt from mandatory COVID-19 testing and the quarantine process upon arrival.