Why would someone buy Grayscale then and not just hold Bitcoin in their Paypal account for example?
See my other comment for a link which describes the play in more detail.
I’m not sure what 40% you are talking about though.
Not to say that Grayscale is really making the world a better place by providing an actually useful service.
https://ycharts.com/companies/GBTC/discount_or_premium_to_na...
It seems the spread is down to 4% now.
And it seems people were willing to pay up to 40% on top of Bitcoins value for GBTC. That is crazy ...