Please remember that you can book your own excursions, minimize bar and spa bills, etc. I easily spend $500 once the cruise starts and although I’d give up a few things, I could whittle that down to almost no additional sales for the line.
We’re pretty low-budget cruisers. Never go to the specialty restaurants, might have wine once on a cruise, don’t buy the beverage packages, don’t use internet, and take very few excursions. So they won’t make much on us — guaranteed. :)