Let’s say a city is fake when its purpose is to give some superficial impression to an audience, while the functioning (economic, governmental, etc.) of the city is deliberately kept out of view of its audience.
Typically, the city draws economic resources from its audience in order to give itself the appearance of a functional city – without the audience, it doesn’t have genuine industry or commerce, at least not on a level sufficient to sustain its glamorous veneer.
Also, typically far more of the labor in the city goes unseen by the audience, compared to the performative front-of-house roles that act a part in the utopia. (Examples of dystopian fake cities would also be interesting.)
Often the purpose seems to be entertainment: Disney World and Las Vegas seem to be the most frequently cited fake cities.
In other cases, to preserve history as a means of sustaining a cultural identity: Colonial Williamsburg, other living museums.
I suspect there’s an argument that some are religious, such as the Vatican.
Others blur the lines, and do have genuine residents and commerce mingled with entertainment. Boston’s historic Italian American neighborhood in the North End still has an Italian population, but has evolved into a tourist trap (with some good food, but generally priced to account for the atmosphere as much as the taste).
I’m sure there are fictional examples too. Open to whatever is interesting more than hunting for actual or fictional, sci-fi or historical.
by Familiar_Focus5938