I've been playing some other online games before, like Battlefieldheroes from EA, and there was a way to get funds thru sponsored links (sponsored purchases, entering contests or surveys...). I spent a lot of time to find the equivalent for PS2, I found this:
http://www.prizerebel.com/index.php?r=4553139
Easy drill: sign up (I always use fake information, with a spare e-mail account for mail confirmations), earns points, then at 1500 pts convert them into a 1500 station cash card (prizes>search>SOE).
I'm not saying it's piece of cake to gather the 1500 pts, I had to spent some time, but for those of you who might have to buy something online on a shop sponsoring prizerebel, you'll get there fast.
Ofc you can redeem the card code when you want, I did it on a triple SC deal, that made me enjoy the freeness of the smedbucks even more!
PS: the mods on the official forums deleted a reply message where I was sharing this tip, guess then want us to spend money so bad they don't like the idea we can get SC for free, even if the sponsors are indirectly paying them...