While I would not prosecute troops for getting a "dutch treat". I as a commanding officer would certainly try and discourage it due to the risks of STDs and the like. But I feel soldiers deserve their R&R and if they want to risk their health that's their foolishness.
You're worried about the remote possibility of an STD for guys who're about to be slaughtered on the battlefield?
STDs are not remote in a third world country such as South Korea.
South Korea is not third world at all, and STDs are far more rampant amoung the American lower classes than amoung Koreans.
From former soldiers I know South Korea was described to me that it was filthy, it stank and the people were poor.
Depends on the region. Overall it is a second world country, with some backwater areas.