You know, this is one of the BIG reasons why DH and I have decided not to take a cruise by ourselves without our kids. We figure if we can't have dinner alone and enjoy ourselves, it isn't worth it. We have been able to get a table just for 4 for our family of four (well one year we were seated at a table for 8, but this was the week after 9/11 and a lot of people canceled their trip and no one ever showed up for that table).
I too wish they would allow seating for just two. We have thought about going and just not going to dinner (eating pizza or room service), and we might do that for a 3 day cruise one year. It is too bad that Disney can't accomadate couples. One of my biggest disappoints ever on the cruise was the one afternoon the DH and I decided to have a romantic lunch at Tritan's (kids went to the Kid's Club). We even told the servers that seated us that we were so excited because we were actually alone for lunch. Within 15 minutes of our 'romantic' lunch two college girls were seated with us. Very nice girls, but not the romantic lunch we were hoping for (and DH and I never get to be alone, we live far from family and have never used a babysitter--we just go out as a family, so this day was going to be really special).
Anyway, I agree, it would be nice if we could go and enjoy the cruise and be seated at a table for two.
DJ