Thought this sounded familiar. I had to do some digging to find these references.
If the idea is to NOT have a universal currency, then that was disccused quite a bit here
. Not to mention, Josh's dev log here
I know these aren't a direct relation, but the information therein is close enough.
What it comes down to, is universal currency is a gamey mechanic needed for gameplay.
At the same time, it is in an economic's power best-interest to be able to trade between them, regardless of currency. Since this is true, I'd assume that races that are smart enough to reach space and co-habitate with other races, they probably are smart enough to create some sort of standardized currency that everyone can use. Of course, that's just my way of getting around the suspension of disbelief.
Early Spring - 1055:
Well, I made it to Boatmurdered, and my initial impressions can be set forth in three words: What. The. F*ck.