There is a 100% premium to the underlying asset, because people are desperate to get into Bitcoin and don't know how.
Is that really the case? In well developed countries it's insanely easy to buy yourself into Bitcoin. I'm from Western Europe, and all I need to do is to verify my bank account, and that's really it. No ID scanning, or other nonsense that you have to go through when signing up at exchanges. I must however note that this service allows me to purchase up to €10,000 per day through the automated system, but this limit could be lifted if I get in touch with them by visiting their location to complete the deal. And yes, it's all legal.