The beverage packages on cruise ships are profit centers, for them. Our upcoming ten day cruise would cost $54 a day for the UBC. We don't drink that much, my wife is almost down to zero now, she'll have a bit on special occasions. Even so, I wouldn't justify that on a cruise ship with what I drink, call it a couple glasses of wine at dinner and maybe 1-2 watered down drinks otherwise, and I do think their liquor is watered down, at least on NCL. We used to get the "free" beverage package until I discovered we can delete it.
And by not having it makes me drink less which is in itself desirable.