I think you've misunderstood. A lot of land vehicles in sci-fi films are just models. These aren't models, they were obviously real working vehicles (not fake "hover vehicles"). Just because Star Wars is set in a fictional universe doesn't mean these buggies aren't real powered vehicles. It's not much different from listing the Batmobiles or the APC in Aliens (which was a converted airport tug) or the things in the Mad Max films, only thing they play a more prominent role in their films. But as I said, Luke's Landspeeder was a Reliant Robin/Bond Bug underneath, so it was sort of a car.

Actually I remember the discussion about a possible site for aircraft and I was against something like the Millenium Falcon being added because it wasn't a real flying vehicle, it was just a model and a completely fictional craft. Perhaps people are against these being added because of a similar logic, I'll just say that at least these functioned as vehicles in real life.