You should re-read the quote. This was not a request for the IP addresses of the users in question, but for the everyone that downloaded any packages uploaded by those users.
You're right. Sorry that I implied that was the only thing they asked for. But the point still stands that it's very common to be compelled to provide the equivalent of "tell me everything you know about this IP address", and our legal has said we (usually) legally have to provide it.
