Cunard, QE2 and now QM2, following in the QE2 tradition, are known for their formality. Why would someone book on QM2, pay the big bucks, and then not have a tux? I paid $200 for my used tux and have gotten more than my money's worth out of it when sailing on QE2 and soon QM2.
Last year, we had a travel agent and her husband at our table. He had a blue blazer on every night, and Weejuns for shoes. He was 100% out-of-place. He and his wife skipped dinner two of the formal nights and even made a rather uncomfortable "joke" about his lack of formal wear. We all wondered if she was one of those travel agents who told her clients that formal wear wasn't really needed on QE2.
I don't understand why people book Cunard, pay for the Cunard formality, and then fight having to appear in formal wear, or nice day wear, themselves. Beats me?
I was also told prior to my first QE2 trip that I would only really need a dark suit. I am so glad I sprang for the used tux! I would have felt out-of-place.