They tried that on a few ships in Hawaii
When I heard the question the NCL America debacle immediately sprang to mind for me too. The Hotel Manager did go a little bit into wages and the fact that some countries are more predisposed to it's citizens going to sea for jobs. People often think Filipinos work on ships because they have no other choices. These people fail to realize The Philippines is made up of a whole lot of islands and shipping is vital to them.
I was really impressed with the Chinese crew members I met. One guy was really a character. He has been on the Rhapsody for a while - even in Galveston. He was very tall (6'2" or so) and called himself "The Booze Man". He worked the dining room every night selling the loving cup liqueur drinks. What a personality! What a salesman! One of our table mates was a retired insurance executive. He said "that guy ought to be in sales. He could make 15k a month selling insurance for me."