Vacations are known well in advance, therefor you can book a vacation destination months before you arrive.
I don't, however, know when I'll be hungry or what I'll be craving months in advance. Years ago, at Disney World, if you were hungry when you walked by any restaurant, sit down or otherwise, you could just walk up and get seated. Now you have to call and make reservations 180 days in advance. In my eyes, this is rediculous. I don't even know which PARK I will be in 180 days in advance, let alone what I will be hungry for. I don't go to restaurants here at home where I have to make reservations days in advance, so I really don't enjoy making reservations 180 days in advance.
Around here we have Applebees, TGIFs, Chili's, Bennigans, etc to have a nice sit down steak dinner. I have never waited more than 20 minutes to be seated at any given time of the day or night. before the DDP, Disney's sit down restaurants used to be like that.
My wife and I prefer to eat when we're hungry, not when we have assigned places and food. At home, when we are out driving and we pass a nice place we say..."Hey, I'm hungry, this looks like a nice place, let's eat here!" We used to do that at Disney World, but not anymore...and I miss that.