Here's the thing about "theme."
People get caught up in a legalistic (overly concerned with technicalities) understanding of theme and ignore the fact that theme is really more about feeling than it is about rules. A good example is the sorcerer hat in Hollywood Studios. Technically, the hat is from Fantasia, a film that was made by Disney in a studio in Hollywood (technically Burbank, but same thing). Thus, you could make the argument that it absolutely belonged in a place called "Disney's Hollywood Studios." The problem with the hat is that it didn't fit in with the feel of the park even if it was technically "themed" appropriately.
Another example would be Splash Mountain. Frontierland is the home of the American old west. Splash Mountain is set in reconstruction-era Georgia. Yet I don't see people crying that Splash Mountain is an outrage that doesn't belong in Frontierland. Why? Because it feels right.
So no, there's technically nothing "tomorrow-ish" about Sugar Rush or Monsters, Inc. Laugh Floor, but I get how video games and monsters fit in with aliens and spaceships in "Tomorrowland." It doesn't feel out of place.
TL;DR...
Sorcerer hat: Fits rules, doesn't fit feel
Splash Mountain: Fits feel, doesn't fit rules