It is funny, I eat at sit down places all the time. I have gotten walk up reservations at Garden Grill, Japan, Mexico, and others. I have also made in park same day reservations or same day in the morning reservations. Even once almost did Canada this way, but in the end decided against it. I have also made 8:30 PM reservations for Germany and walked up at 7 PM and asked if they could take me now. I have done this 3 times and twice they could take me. The 3rd time was in the middle of spring break, so I don't blame them for not being able to do it then. If you learn to play the system, it really is not as bad as most people say. They don't let empty tables sit. If they have cancellations or an open table they know they don't have a reservation for, they will take you. I was in line for the one on main street, the people in front of me got in w/o a reservation, but that was their last non-reservation table and therefore we could not get in. Heck with my son we needed handicap seating and it needed to be large enough for a double stroller and even with that restriction we still managed to get walk up seating to many places.
A secret for those hard to get places. Most of them require 24 or 48 hour cancellation notice. So go into the Disney online reservation 24 or 48 hours in advance and you would be AMAZED at the reservations you can get last minute for those locals who don't know when they will be going to the parks until closer to the day. For those places that don't require that far in advance cancellation, you can normally get morning of reservations, in park reservations, or even walk in.
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