The game being a big hit in SK is nice theoretically but doesn't mean you can afford to develop patches or sequels if nobody is actually buying copies of it.
SC was successful in large part thanks to the community, so maybe to replicate the success, game developers need to figure out how to recreate the same thing and coexist with a robust community. I think monthly subscriptions are an absolute blocker for some great community contributions, for example.
What are you talking about? At least 4.5 million copies were sold in SK. The question is, did lan clubs reduce or increase the sales? It's hard to know for sure, since no AB-test was made but I strongly suspect that they did increase the sales by a huge amount even if the clubs themselves didn't buy a single copy. Give 'em the razor, sell 'em the blades.