Ive heard several people tell their retired parents get last minute (within days of departure) deals on cruises by being walkup/standby buyers. Cruise line just trying to fill the boat to pay taxes, sell alcohol and get gamblers.

I think we experienced this on a Christmas cruise a few years ago where you could see tons of cabins available a week or two out and we were hoping for an upgrade across the hall from our inside. But sure enough they filled that boat.

Do you drive up to the port?, some office? The Carnival Corporate Office (for all their cruise lines Princess, Carnival, Costa)? Is there a travel agent that specializes in almost free cruises?