On my last cruise in September on the Seaside as a solo YC cruiser, I was NOT able to invite a guest to share dinner. In fact, the waiter in the steakhouse was very rude about it in front of my guest. I was made aware of the situation by my butler prior to going to the restaurant that I had to pay for my guest and was prepared to do so. The problem was the waiter made an excessively big deal that I needed to pay for the meal for my guest, that it was embarrassing. I had asked this question on this forum before the cruise and the consensus then was "no problem". That is not the case!