First of all, Rock 'n' Rollercoaster is at Disney World, in the MGM Studios theme park, now known as "Disney's Hollywood Studios."
Also note the detail that Disney puts into creating the parks. There are so many built in details that they are lost on most visitors. Did you know the pavement in DinoLand, U.S.A. has a story behind it? Since asphalt would melt in the Florida sun, they poured concrete into it, dyed it black, and put chicken wire in it to make it look like a cracked highway.
The streets of Adventureland and Main Street are PHYSICALLY different, and have more texture in them to make it seem like you're on a rocky road.
And don't even get me started on the Animal Kingdom...