I wish other games that I know I like would do this...
First one that comes to mind would be Aion. I wouldn't mind paying a 1-time fee for that.
Part of that fee is just for convenience, too. It's not just "oh, what if I don't like it?" You're essentially paying for not having to pay repeatedly, if that makes any sense. I can see how it would be bad for some games when people decide to quit early, but on the other hand, I can see how some people would definitely get their money out of it.