Unacceptable BS: In order to be ready to repeal another June 1950 style invasion from North Korea the Republic of Korea must maintain a constant state of readiness and the only way to do that is drilling and training.
What the Chicoms, Russians and Norks are demanding is South Korea’s surrender to the North’s proven blood lusting tyranny.
They’ve made it very clear that their objective is the conquest of the south, too. For example, the repeated digging of invasion tunnels across the DMZ. They’re worthless except for in a first strike / attempt to take over the south, because if the south strikes first and pushes them back, then they lose access to the tunnel entrances. They’re only useful in the event that the north decides to try to conquer the south.
And they made a lot of them. Which makes their motives very clear.