Hi Joe, I spent a couple of evenings with a two Korean couples after walking similar stages, they had reasonable English but I had non-existent, Korean. They suggested that not all pilgrims were religious, but they were, and all Koreans I met gave me that impression, they indicated that following the increase in Christianity in Korea there was an attraction to walk in footsteps of early generations (as they put it ). They explained to me the history of what had happened in Japan and China and contrasted it with the historically more benign environment for Christians in (South) Korea.
With regards kit, I had a slightly different experience in as much that the Koreans I met all had the latest gear, often colour coordinated, ( as in video above), smart phones, cameras, poles, compeed etc.. etc... they were very well prepared and clearly had a lot of prior knowledge presumably from their own forum. I wish I had asked why so many seem to come early in the year when snows and rain are more prevalent, do you have any idea?
Buen Camino