There are planes in Remnant, too. Even jets. It's a lot easier to ride airships, though, since the number of people you can transport are a lot and there are also a lot of amenities and rooms.

[ At least, she assumes the airplanes in Midorima's world are the same as most planes for travel where she's from. They can keep talking about this or talk about something else until they reach the park, in which case Weiss hops down and pays the guy a few sylvs for bringing them there. ]