My only guess (which is a bit far fetched), is that they somehow want to influence Google's search engine. I recall some years back that particularly enthusiastic people were able to change Google's results by swarming it with the wrong links. E.g. Searching for "Easter" gives Easter egg results. But they could keep on clicking, say, "Kitten" results and eventually, Google will show kitten results for Easter.
Later on, Google updated their algorithms. They now provide results for that which is most linked to. If I search "Butterfly", Google will show me a helpful wiki about butterflies because that is what most people have linked to. Google ranks searches by their reputation through the number of places that have linked them.
I think that's what the K-bots are doing here. They link to casinos, so if someone searches for Korean casinos, Google will see the massive number of links on our site and thus say "Xyz. com" is a good Korean casino.
At least that's what it looked like based on a computational algorithm article I read some years back. Google might have updated their algorithms since, and so may have spammers.
GambolMuse
Iluvtoji