Not exactly. If you purchase a beverage package before you sail, it must be purchased by everyone in the cabin. If you wait and purchase on board, it does not have be purchased for everyone in the cabin.
totally not true. i always purchase my beverage package on royal before we cruise; DH does not get a package. the requirements for both to get the package were changed a couple of years ago; now everyone can get a different package or, like me and DH, one person get one and one not. it doesn't matter whether you buy it onboard or pre-purchase it before you sail.
OP, thanks for the review. my NCL gem cruise was, quite frankly, pretty bad, but i'm intrigued by the big new ships and considering trying one out.