Celebrity is one of the few lines you can purchase different drinks packages if sharing a cabin.
My wife stuck to the 'included' Classic package last time as she does not drink a lot of alcohol nor is particularly fussed over quality, whilst I upgraded to Premium. This worked perfectly for us. We have done the same for our cruise next year.
No, you CANNOT purchase drinks for others using your premium card but your partner can pay the difference if they fancy a particular drink that is over their Classic limit. My wife tried a cocktail in the Silhouette's 'World Class Bar' and paid t