NCL Newbie - confused about additional fees?

Celebrity for instance won't let you pay the difference if your drink is over the limit unless you have their premium package, and only the classic is offered as a booking perk)

For DH and I for the fee at sea promotion, we did not get the free at sea drinking package, as we typically just drink coffee and tap water and even if we do on occasion order a drink, our total costs would be less than the 18% additional charge on the package, as it's 18% on $69 a day. If you spend a lot on drinks, though, normally this would be a fantastic free at sea option. The prepaid tips was a great perk for us, as we would always pay these anyway, so that was of benefit. We also got the specialty dining free at sea perk, which is fantastic as it gives three specialty meals, the same number we wanted to do. We will be very satisfied to do the MDR and buffet on other days. O'sheehan's is also a complimentary restaurant.

That is very helpful thanks! So, I'm thinking the drink package is a great perk for us. I read about the "waterfront" - can you use the drink package there too? (sorry for all the questions! I'm just so new to NCL!)