Yes, for breakfast and lunch.
We had breakfast there yesterday and a gentleman stepped off the elevator before us and simply asked to eat at the bar (no reservation) and they pointed him to it immediately. He clearly didn't care anything about the characters (I watched out of curiosity and he didn't even turn around to look at them!) but wanted a nice meal.
When we went for dinner, people inquired and were seated there without a reservation, too.
Also keep checking! They pop up a LOT and you can set up a reservation finder to make it easier.