You can buy insurance privately. Insuremytrip is a good place to start to compare policies.....
We were on the Hurricane Jeane cruise that went from a 7 day cruise to a 4 day cruise out of Ft. Lauderdale. Not complaining--DCL did all they could for us. We got a 40% refund on the cruise fare portion of our ticket (mailed to home after cruise) and a $200 per stateroom onboard credit. Unfortunately no upgrades because many Wonder guests were moved to the Magic. We were also given free bus transportation from WDW or MCO to Port. Lauderdale and from Port Canaveral to either WDW or MCO.
We were at WDW the week before....it cost me every penny of that refund to book the additional days at WDW and spend them locked in our resort with instructions not to open the door. We had gotten a discount on our original WDW package--no discounts on emergency storm bookings! Again, WDW did all they could do. All the TV channels that normally run "company clips" and other ads were changed to movie channels--one ran a loop of 6 "little kid" movies, another ran "big kid" movies and a third ran adult type Disney affiliate movies. We had periodic updates on our phones.
OK, so what did insurance cover? Actual cost of the room and food at WDW or 1/7 of the cruise cost for each day spent at WDW...whichever was greater. I guess they figured they had to go with the "greater" because locked in a resort room wasn't exactly the vacation we'd booked. It didn't matter that DCL had given a partial refund--that wasn't taken into account on the insurance calculations. Another lady I met on the cruise said that her insurance was paying $1000 per day for the missed days. Of course, what they will cover is up to the maximum you put on the policy. It would also cover canceled/change fees, etc. for flights provided you bought a high enough dollar level on the policy to include the flights.
What I mean is....hypothetically you could have 2 people in a cat 12 each paying about $1000 for the cruise (I'm using round figures to make this an easy example). You could buy a policy that would cover up to $2000 in which case this is the maximum you could get back. OR you could pay for a $3000 policy that would cover the cruise plus airfare. With some private insurances, they will cover the cost of the cruise as if you had paid with cash despite the fact that you booked with points.
The other reason to think about insurance is the fact that many health insurance plans exclude anything outside of the US! Your trip insurance includes coverage for medical issue that occur on the trip, lost luggage, etc.
DCL also gave us to choice of canceling the cruise and getting a full refund or rescheduling. If you purchased air thru DCL, they helped with new air arrangements, but if you bought air on your own you were responsible for getting to one of the airports (either MCO or Ft. Lauderdale).
All this said, we have sailed many (I think 6 or 7) times during hurricane season and only had one cruise negatively impacted by a storm. We did sail a modified route on another cruise as the captain was taking us away from a hurricane.....but it was a great cruise.