^ Well at first Sunnydale was just described as a "one-Starbucks town" then they just kept adding things and adding things (a university and an airport as the main offenders.)
They did the same thing in
Smallville. It just kept becoming a bigger and bigger city, and even acquired its own university, which was separate from the U. of Metropolis, even though by this point it had been established that Smallville was just a couple of hours' drive from Metropolis at most (and by the end of the series it seemed to have migrated into being a suburb of Metropolis).
At least
Sleepy Hollow had the sense to make its fictionalized version of Sleepy Hollow/Tarrytown much larger than the real one from the start, so that it'd have enough people and institutions to drive any needed stories.