Actually you now need to give a credit card number to secure a reservation at sit down dinners. I am sure that this is so people do not overbook as you are charged $10 per person for not showing up for a reservation. Funny thing is we don't do Disney dining and didn't make dining reservations ahead of time (too hard to do with fast passes, weather conditions, energy levels, 15 people in our party etc.). So we have been able to walk in a few places or make same day reservations at some too. Last night we went to Sci-fi at HS. It was about 5:15 and we were a party of three. We enjoyed our dinner but noticed that the restaurant was only about 65% full. Lots of empty cars. (I can remember the old days when there was nary an empty car and the place was hopping!). Several cars remained empty the entire time we were at dinner. The server said they were most likely for reservations. Seems crazy as when we left I heard them tell a family of five they were no longer taking walk ins only guests that had a reservation. We also noticed this at Tonys in MK, Turf club at Saratoga Springs, Tusker House at AK. They were turning away walk ins but they had lots of empty tables "for reservations"