Take Las Vegas for example — roughly 70% ish of the Vegas metro area population is actually in the city of Las Vegas which has an unusually large city limit.
In the Vegas Metro area, you really only have Las Vegas, Henderson and North Las Vegas — that’s it. Perhaps you could include Boulder City but Boulder City is disconnected similar to Tooele being disconnected to SLC.
Summerlin is often micharacterized as a city or suburb of Las Vegas but Summerlin is not a city — it’s a development similar to Day Break in the Salt Lake Valley.
Vegas is not like Salt Lake City or other cities where there exists a multitude of suburban municipalities. In the SLC metro area you have many cities like: Magna, WVC, Sandy, Draper, South Jordan, Kearns, West Jordan, Herriman, Riverton, Bluffdale, Murray etc… etc… which doesn’t include other communities that are technically part of the official SLC metro area such as Tooele area communities, Park City, Davis county etc…
So when people look at SLC’s roughly 20 square blocks it gives the appearance of a much smaller population than it actually is.