Hi Zee, welcome to Cruise-Chat. Congratulations on your upcoming cruise! The dress code in the dining room when it is not formal is smart casual. Sundress, pant suit, nice slacks with a nice blouse for women. Slacks, dockers, not jeans with a polo shirt or nice shirt with collar for men. Johnny Rockets does charge, I believe the cover charge is $3.95. Hope you have a fantastic cruise, and once again, welcome aboard!
I, for one, am on vacation and refuse to own or rent formal wear. I was told the last two times that we were on MAriner that even on the formal nights, we were NOT required to dress formally, and that the normal casual wear for men was fine and dandy. We even had our pictures taken against the nice backdrops, with slacks and a polo shirt for me, and my wife's normal casual wear. I know, and understand, that there are other who like to dress up for the formal nights. I don't bug them, and they don't bug me. We're all on a cruise, so we all get to enjoy it at our leasure and pleasure.
Have a great time-you'll love Mariner.
Sometimes I'll just wear a sport jacket on formal nights, but that is very seldom. I'd feel out-of-place if I didn't dress up some what. A sport jacket looks good with or with out a tie. If I were going to wear casual clothes on a formal night I would head up to the Windjammer.