Yeah, but they know the truth is there aren't enough fans of most of those other factions to make such a sub-line financially viable. It's the same reason they don't let sub holders opt out of any upcoming figures they don't want, because Mattel know damn well many of these niche pieces wouldn't sell enough to be justified in being made unless a good percentage of collectors were basically being forced into buying them.
Personally I give the line until 2014. Next year is locked in of course, but I predict an even bigger drop off in 2013 as far as subs and sales and just plain line fatigue goes, and much doomsaying to go with it. And the fact that this line isn't new collector friendly (and even less so as more time goes on), so lost buyers aren't exactly readily replaced by new buyers, doesn't exactly do it any favours either.
I think 2014 subs will be the final 'call to arms' year, but while they will scrape enough subscribers to go forward, they still won't get enough of a boost for Matty to see the line as viable beyond that year.
Oh, and when the line does collapse, it'll be all our fault and Matty will blame us for not supporting it enough, despite the thousands we've pumped ino it over the years at that point, and the often inept way that Matty has handled things...