If you are buying a package (not a
free dining one) then you can add dining by purchasing a 1 day park ticket for each guest (It does not have to be a hopper). Sometimes, specific promotions, i.e. free dining, require a ticket for every night of the stay. Another option if those will be wasted tickets is for 1 person to get an AP. You may be able to save more $$ on the room, and add dining without buying the 1 day tickets for everyone else and come out ahead money wise this way.
E.g. we saved an additional $200 on the room with the AP discount over the 40% public discount. 2 of us had non-expiring tickets and did not need the 1 day tickets. That made the AP worth the upgrade for us. DH was going to buy a 7 day hopper anyway.