I am foremost a Combat Mission player with Band of Brothers.
www.webandofbrothers.de 
Combat Mission is Battlefront (BFC)'s sugar baby.
Around 1999, CM Beyond Overlord came out, went "huge", nearly cornering the 3-d non-RTS tactical market. Then came CM Barbarossa to Berlin. These game were sold via a combination of store and website.
The CM Afrika Corps came out. This was sold entirely on the website. This product did exceptionally well. After CMAK, BFC started getting a lot more third party developers to publish with them, solely on the website.
This is a fantastic job of marketting themselves by BFC, leading developers into thinking that their success with CMAK could be general success.
However, the CM series is special. It is CLEARLY an unrivaled product in its niche, with no bugs and virtually 100% community support. This leads me to think that almost everyone who plays CM bought CMAK.
However, DW is different because the SC community is not committed to DW, and it does not enjoy the same "1000lbs gorrilla" status in it's niche. Thus, because SCS missed the SC community as a whole and failed to market to people outside the community, who may not have bought it anyway, sales are dissappointing.
How was SCS to know that the SC community wouldn't want much to do with DW? At least, that's the feeling I get, coming to it rather late...