Returning to established ideas in a game campaign provides an anchor for the players - something familiar that they understand, within the rules of the setting.
So consider giving the familiar a twist! It looks like the same phenomenon, but it's not the same explanation.
Example: If vampires are an established thing in your setting, and the players have learnt the usual facts about them, introduce something that looks like vampire, quacks like a vampire, but isn't a vampire. It's some guy with pale skin and a pathological thirst for blood, but he's just a human and has no supernatural powers.
At any point where the players are expecting something, you can toss in a thing that resembles it. They may jump to conclusions and things may go haywire because of that. It'll be a lesson learnt. Or maybe not, given how eager PCs are to jump to conclusions.
Commentary by memnarch (who has not seen the movie)
Oooh, this looks pretty nice. And suspiciously not like a military complex. Those buildings look too close together, and there's the big tower in the middle of the scene. A waterfall would be defensible by land, as would the mountains, but this is Star Wars where starships are cheap and hovercraft are cheaper! And Kanata is supposed to be fighting or hiding out here? Comic-Kanata said he was trying to take out a gang of some kind; maybe this is a gang town instead. Hmmm. Or maybe a secret military installation? I suppose that wouldn't be too far out of the realm of possibility, but it would be quite a bit different than what Star Wars has done so far. Those have all been hidden in out of the way places when they aren't obvious; underneath random cities doesn't seem right. And I guess technically Kanata didn't say he was here on Canto Bight, just that it was a casino, so maybe that's also a bit out there as a possibility as well.
But all of that still wouldn't cover why the characters came here in the first place while the Resistance fleet is still being chased! Sure, Episode V had something similar, but that was after an immobile Rebel base had been attacked and there were enough little things to make it feel like the main characters weren't abandoning the last of the organization. Did they come here to try and get more people to join in the fight? A bunch of gang members might be willing to fight The First Order, but there'd need to be some really good reasons to do so. And that would still somehow need to match up with the comic story coming here for the PCs to make a bunch of money.
....And now having thought about Cloud City a bit more, I'm wondering if this is meant to be the equivalent location in this movie. If so, I'm hoping there's something I'm really missing out on from the movie dialogue. At least Episode V had the constant Millennium Falcon problems to encourage a stop somewhere not inside an asteroid.
Transcript
GM: Let’s cut back to Rose, Finn, and BB-8.
GM: You approach the desert world of Cantonica.
GM: The Canto Bight casino complex is built in a stunningly spectacular location, on a bay high in the mountains with majestic waterfalls, where it’s perpetually sunset.
Rose: So it’s like Naboo, where tidal forces push water up through springs and geysers, replenishing this improbably high-altitude lake?
Poe: Nah, it’s always sunset, so the planet must be tidally locked. It’s a desert because it’s always hot on the day side and water will freeze out on the night side. No chance tides could feed mountain springs.
GM: Uhh...
Poe: Obviously they’re pumping the water back up.
BB-8: It’s a giant infinity pool!
Finn: Wow. This place is even more decadent than we thought.
GM: Yes. Yes, it is.
Rose: One day lack of prep is going to backfire on you.
GM: No more than actually prepping anything ever has.