The service staff work for tips. No wages. No benefits.
I was shocked when I first heard this. I asked around, a lot. Everyone confirmed.
I personally hate the cruise ship experience. The master/servant dynamic makes me very uncomfortable.
That their working conditions are only mostly terrible is sufficient for me to act on my values.
I'll give analogy. WalMart screws their workers, their suppliers, and their host governments (and by extension us tax payers). Not in every case. But enough to piss me off.
So, yea, I'm not shopping at WalMart. Maybe they're not all bad. Sorting it all out is too much work. Especially when I have plenty of options that are mostly good.