First, I'd also like to welcome you to cruise-chat. I hope before you tackle this again with the agent or make any changes, you read this post.
The military rate is available to military personell and Carnival does not discourage what your mother has done with the CCL Rep. Nobodys job is on the line over it or anyone scheming Carnival's policy. This type of shuffling is common through both CCL direct and every agent and agency in existence, at least all that I'm aware of. Just like the policy of having an adult responsible for each cabin does not mean one has to actually be in the cabin, there are no cabin police onboard. For booking purposes only, all passengers have to be 21 (unless one is 21 and married to the 2nd who is under 21) or over to occupy a cabin or at least one has to be 25. That's carnivals rule for age. Parents often split the booking and put an adult and a child in each booking. Then depending on the age and responsibility of the kiddos, the parents are free to occupy a cabin and allow their under 21 kids to occupy the other. There is, that way an adult responsible for that cabin and whoever occupys it. I'd be a little concerned about 18 YOs on deck 1 and all the adults on deck 6 or above. Not for the teens but for any rowdyness or noise (teens will be teens if there is no supervision) for the other passengers on deck 1.
Similarly, CCL does not discourage splitting veterans in order to get the lowest rate for each cabin in the group with many veterans. They actually, as happened here, suggest it often. I'm not going to read the 15-20 pages of their terms and conditions in their passage contract but am willing to bet there is no expressed or implied rule against this practice. If there is, it is null and void by the common nature of the practice by CCL themselves. In fact if you had a circumstance where it could be done and was not offered by their agent, there may be a problem for the employee for not finding a way to get the client the lowest rate for their group. That is the job of the agent and the direction given to agents. It's not, at least in this industry, manipulation of rate code promos or rules. It is allowed and encouraged. Each military person sailing is entitled to a cabin on the ship at that rate.
Sorry for the long post. Just didn't want the OP to think she or her mother is doing anything unethical or against CCL policy. Keep the military rates and fix it at the Pursers desk so key cards will match cabin #s, you'll have no problem. But I would spend the difference to get the 18 YOs up to the deck with the adults, no matter how responsible they are at home.
One other note. Dwayne mentioned that they recently opened their "Friends and Family" promotion. Allowing military rates for add'l cabins. I'd call the agent back and ask if it can be applied to your bookings. Sometimes there will be an asterisk *Applies to new bookings only, effective on bookings made XX/XX/XX and after. If it can be applied, you may well be able to get the military rate for all 5 cabins now.
We did a Military Booking on the Spirit about 14 months ago. They allowed us to book an extra cabin for my Aunt and Uncle. They were first time cruisers. There we not problems, we both book 8h category. It seems to me that re shuttle of people would also create a nightmare as far as the sign and sail cards go.
TrvlPro, put it it better than all who responded. I too had this concern, my teens in a room alone, after reading so many places there had to be someone over 25 per cabin with minors. We leave in about three weeks and it was a major issue for me, the rule. After talking with two different agents, I got the same answer as long as they are next door to me and it's noted in Carnivals system that they are siblings, everything wiil be okay. In your case they are friends, so it may be very important that you do check again with Carnival. I do know that the agent was adamant that she couldn't book minors in seperate cabins without them being either right next door or atleast directly across the hall. If all fails, put the girls in one of the other cabins on deck 6 and the older people on deck 1. I may be repeating what somebody has already said, forgive me. Don't wait to the last minute, Carnival I undestand is very strict on the room policy age restrictions Free Cruise Tickers
Some teens are responsible enough. When I was 19 1/2 I could not do many things because of my age, drink, gamble, vote (voting age was still 21), rent a car, buy a smoke (didn't want one anyway), and the one that really bother me, get a Govt job. Why should those thing bother me you ask. I was 19 1/2 and a Combat Vietnam vet...
Gary, thank you for your service. I agree that there are many responsible teens and the laws that allow young men to fight and die for their country but not to have a beer on the weekend don't make much sense. I also know that I was very responsible at that age when I was at home and anywhere someone might know me. I cared about my reputaion, consequences and actually cared if my actions would reflect on my parents and their good name. I also know I took a couple of trips with my buddies away from home where nobody knew me or my buddies and we did some things I'm not very proud of on those trips. Peer pressure and lack of supervision can ****** good judgement in young people. I was no exception even though I would have considered myself independent and told anyone who asked that I didn't follow the crowd and made decisions for myself. Clearly in hind sight, that was not always the case. There is a reason Carnival and other lines want cabins with under 21 passengers next door to or across the hall from a parent or guardian. I'm sure there are some teens who would always do the right thing, I just have to believe from being an observer of society today they are not as common as they once were.