Turns out lack of regulation is a double-edged sword.
On the one hand, the quality of pirate sites varies wildly - with some being virus infested hellholes.
On the other hand, there's no legal bullshit to get in the way of them providing their service. Their competition can't easily just cut them off from content.
And because they're operating privately rather than publically, they're incentivised to operate sustainably rather than chase quarterly profits - which oftentimes benefits their "customers"
Exactly. You've got limited time to tell your story in a movie, so establishing a fake currency that nobody except hardcore numistatics nerds will care about is kinda pointless when everyone already understands that credits = future money.
And as you say using a real currency doesn't make sense in most future movie contexts, and using the "wrong" one may even offend some people who may then boycott your movie - which is obviously not desirable when you're a studio trying to make money.
I image its the same reason for the Gold/Silver currency in many fantasy settings.