I didn't take my son to signature restaurants for quite a while. One of the only ones I felt comfortable doing when he was a baby was The Brown Derby. Because that's in a park, I expect other children to be there, and I've always felt the noise level to be higher there than in other signatures, just based on that fact.
But, Citrico's is one of my favorite restaurants on the property, and I avoided it like the plague for years, because I didn't want to take away from anyone else's dining experience. Last year, I finally decided to bite the bullet and do it.
Well, did my son ever surprise me!!! (He was three and a half at the time.) He was extremely well behaved, and I had plenty of things for him to do, so that was not an issue. I've eaten in signature restaurants with him since, and quite frankly, he behaves better in those than in some of the others. Not sure why, but I think it has something to do with the selection of food options for kids as well. He had a wonderful fruit / cheese / cracker plate at Citrico's that he just loved, and so a well-fed happy kid makes for a relatively quiet well-behaved kid in our world. (We both get cranky when we're hungry.)
I only had one incident on a trip in December where I received the evil eye from another table during our whole meal, and that was in Chefs de France. And honestly, my son was not out of control, at all. He was sitting at the table, not running around, not being obnoxious, just playing with his matchbox Disney cars. And every now and then, a loud Vroom Vroom would come out of his mouth, and they'd give me this look. At which point I'd explain to DS that he needed to use a quieter voice in the restaurant, and he would. But sometimes, happy little boys forget themselves, and they make loud noises. And quite frankly, the level of noise in Chefs that day was pretty loud, so it wasn't a situation where you could hear a pin drop.
I'm hyper-sensitive to this issue, having felt so badly during that dinner, when in all reality, you're dining in an establishment where there are children. And if you want to dine in an establishment where there aren't, then maybe you really need to rethink where you're vacationing.
I understand that not every parent is like myself and my husband, and they're maybe not as on top of things as we are, and then again, we all have our moments.
But when I go to Disney World, I expect to see children in restaurants. I did even before I had kids, and it never bothered me.