The termination emails were part of a phishing scam. Bit of wonky reporting there.
Without piracy RapidShare wouldn't have a business. The whole thing was founded on illegal file sharing and recently they have obviously found that people will be willing to buy a premium account to still download files once they put up their no free download slots available message. Got 9 out of 10 parts of something and they tell you it's pay up or maybe not get the last part and people seem to pay up.
It is a big step though to expect people who can download anything they can find on a forum for an annual RapidShare fee of $75 to actually start buying things. Everything on the internet is very fluid and I don't think people have brand loyalty to sites as much as to brick-and-mortar shops. Make it too awkward to get something from one place and someone will move in with a different upload/download site or method with an attractive incentive scheme and the big uploaders just move. They already have everything pretty much automated, both the uploading and forum spamming their links, so changing filehost won't hurt them much at all.
Seen more and more hotfile links recently and only after looking just now have I found they have an
affilliate scheme with $$$ for high download numbers. With all the forums there is a huge promotional network and it wouldn't surprise me if there are people with $1000+ a month coming in from sharing stuff and aggressively posting it everywhere.