On your sample cruise you note that $336,000 in tips are collected. That is only $48 per crew member per day, assuming 1,000 crew. That’s not even minimum wage anywhere in the US. Most of the service staff make far less than $500 per month as a “wage”. With tips, that less than $2,000 per month for working 12 hours most days. On an hourly basis it’s around $6.40 per hour.
Justify it any way you want, some of you are just cheap.