I went on a cruise recently and my roommate had to cancel for health reasons. Princess cruises wanted to charge me the single supplement even though they did not refund my roommate any money. My TA had to argue with them so I would have the room without the single supplement.

You were right in having your TA go to bat for you.

I love cruising but it's getting harder and harder to defend some of the lines.

If your roommate would NOT have canceled and simply NOT shown up, there would be no issue. The line would have simply not given him a refund and would not have thought twice of charging you extra for him not showing up. They got their money....

Them charging YOU extra for him canceling is charging twice for the same fare!

Again, bravo for standing up to them on this one.

I had the same thing happen on Silversea. Didn't fight it too hard, though, because travel insurance covered both my roommate's fare and the single supplement. The insurance company told me that this was standard industry practice. They're the ones who paid, so I guess it's up to them to fight.