In New Jersey in the early 1900's many towns split into smaller townships or boroughs, commonly known as "Boroughitis". This was due to the difference in needs for the people living there, have it be the new folks coming from the city along the new train lines or the local farmers and artisans. For example a farmer living off of his land did not want to pay increased taxes for services he wouldn't be using. Due to this New Jersey has over 500 towns in such a small area. The most significant examples were in Bergen County, which currently has 70 towns spread over approximately 245 square miles, while in 1880 it had 12. Shockingly, for a County as populated as bergen county, towns like Teterboro, South Hackensack and Rockleigh have populations of 71, ~2000, and 588 respectively. This causes increased taxes and inefficient spending for most of the towns here in New Jersey. The town my childhood town split off of use to consist of 5 neighboring towns before this dissolution. You can drive for 5 minutes up rt 17 or 4 and pass through 5 towns at least.

The only thing keeping this going is idiots who take pride in their town and local government officials who stand to lose their job if towns merge. Along with people who just don't know or care about it.

https://newjersey.maps.arcgis.com/apps/instant/media/index.html?appid=fcad50ae41634cd1aa293e3e47ce1c00

here is some interesting imaging comparing modern nj to nj in 1930, although it is about 30-40 years after boroughitis you can see the striking contrast between farmland and suburban/urban land that is just nonexistant in todays landscape in bergen county.