Sure, but the difference here is the pirate is claiming it's "their data" and asking for donations.

Well, it is their data.

The word "their" is overloaded, it could mean "thing I have the legal right to", or, "thing I have in my possession right now".

The latter condition is clearly true. It's their data.

If you pretend the other definitions of possession don't exist and claim "aktually it's not theirs they don't have rights to it" then that's on you for faking an incomplete understanding of language.