Funny how they threaten you not to do a billing chargeback by putting your name on "some list". I'd say it is a scam, simply because if you google the name all you get is their site and this thread on A.net. I'd assume that any normal, respectable company would have more sources referring to them than one thread in a forum.
So what was it they billed you for, and how much?
All the things you probably hate about travelling are warm reminders that I'm home