Real question: Why don't Korean car companies lobby against the metro? Same in Japan. In the US, the car companies were heavily invovled in the demolition of some mass transit (post WW2).
When an entire nation has bought on the idea that X is desirable, lobbyists can only go so far: you might as well ask why American factory owners don't lobby against Thanksgiving breaks.
Another complication is that subway stations reliably increase real estate prices, and in Korea everybody desires higher real estate prices for their town. (Of course we then complain that the prices are too high and vote for the opposition. And then we demand the new government to increase real estate prices just for my town. The cycle continues. Don't ask me why, it's a whole can of worms.) In Korea, a company lobbying against subway would fare about as well as a company lobbying for real estate tax hike, that is, very poorly.
