It's a dirty little secret in the cruise industry. The crew members in tipped positions are essentially not paid by the cruise line. The cruise line pays a token salary (and provides room and board) to Dining Room Servers, Dining Room Assistant Servers, Dining Room Head Servers, and Stateroom Hosts/Hostesses.
I've seen various numbers in various articles... $50 per month, $80 per month, $50-75 per month, $75-100 per month, and so on.
Check this article from 2006. It's primarily about Carnival Cruise Line, not
DCL. But the basic idea is the same across the mainstream cruise lines.
http://the.honoluluadvertiser.com/article/2006/Jan/01/bz/FP601010311.html
The article starts off like this:
Imagine leaving your spouse, children and home for 10 months a year to work for tips aboard a cruise ship.
That's the choice made by thousands of workers on ships based at Port Canaveral, Fla., and other major ports. To support families and gain hope for the future, they work 12 to 16 hours a day, seven days a week for 10 months at a stretch — some for salaries as low as $75 per month.
Passengers are expected to pay directly for the service they receive from these crew members through cash tips (or monetary tips charged to their stateroom accounts). It's called a tip or gratuity, but it's really how these crew members are paid. That's how it works on the mainstream cruise lines, including DCL.
With tips, the crew members can make far more money than in the developing countries that they come from. They can support their spouses and children better than if they worked at home -- but they don't get to be with those spouses and children.
I understand that DCL is a more desirable cruise line to work for than some of the others. For example, DCL provides uniforms instead of making the crew members buy them out of their their pay (in other words, out of their tips). It's very hard work, with long hours. In that way, DCL is like the other cruise lines. The tipped crew members on DCL work 12-16-hour days with no days off for many months on end.
You do not tip directly for service at breakfast, lunch, counter service, snacks, and buffets. Instead, you only tip your 3-member dinner server team (and your Stateroom Host or Hostesses), but you're really paying for the work these crew members do all day.
The system works! The tipped crew members have an incentive to provide
outstanding service, and the cruise lines have a lower cost structure.
The service tends to be so good that many passengers (probably most passengers) tip above the suggested amounts.