Absolutely not. People cancel all the time and the nearer it gets, the more likely that is. Keep checking back - even while you're there if you have internet access.
We hate being tied to ADRs and, with 20+ trips under our belts, there's nowhere we're really desperate to eat at these days. We've found it's perfectly possible to get in as walk-ups, particularly at slower times of year such as this. To maximise your chances, steer clear of the peak hours. Some restaurants open as early as 11:30am for lunch and that's when they're at their cleanest!
Am I right in assuming it's just two of you; no kids? Now that we're child-free Matt and I are partial to eating at restaurant bars and, as you can't make reservations to do that, it's usually easy to rock up and be seated straight away. Favourites include The Crew's Cup Lounge at the Yacht Club, The Wave bar at the Contemporary, Cafe Rix at Coronado Springs, Territory Lounge at Wilderness Lodge, Victoria Falls at Animal Kingdom Lodge, and T-Rex Cafe and Raglan Road at Downtown Disney. Fulton's has a really nice bar, too. Ditto Paradiso 37, although I've never tried the food and it doesn't get rave reviews. What about the sliders bar at Portobello? Sanaa at Kidani Village has a gorgeous bar area. Flying Fish Cafe is another possibility. At bars which are part of restaurants, you can choose from the main menu; standalone bars have much more limited menus.
This year we're going to try for an early lunch at the bar of Yak & Yeti. It's one of many places where we prefer to make a meal by sharing a selection of appetisers, rather than order entrees. So often we find ourselves saying that the starters are superior to the mains. Having seen a photograph posted by a friend on Facebook of the Wagyu Beef Cheeseburger Flatbread at the California Grill, we're thinking of popping up to the bar there for an early dinner. Again, it's from the appetisers menu, but the bar staff are used to diners choosing to do that. We have done the same thing in the main restaurants on occasion, but it seems more fitting at the bar somehow.
ETA: A feast of appetizers at Yak & Yeti (Seared Ahi Tuna, Pork Pot Stickers and Lettuce Cups for two, say) would set us back around $23. We'd have to fork out a similar amount for sandwiches at Pizzafari with all the charm, and slightly less taste, of a cardboard box!
Theres a lovely Italian called Maggianos (I think thats the spelling!) near Pointe!
as we fly out next Sunday. 
