Yeah, I've noticed a lot of software is like that. Just never realized that put them in contention for award-winning Fiasco status. < shakes head >
I think they meant you must use the same computer to run it every time as it has your persona information on it. They may store some data client side.
Persistent worlds usually save the data server-side so you can play on any computer that has the client installed anywhere in the world as long as you have your account and password names.
They probably did this to cheap out on server space.