New Jersey

Manchester High School incorporates the towns of Haledon, North Haledon, and Prospect Park. Each town contributes to the school system according to its aggregate wealth of residents.

A few years ago, North Haledon wanted to break its compact with Manchester and to send its children to Midland Park. Midland Park is in another nearby county. It is more upper middle class. It is more "white." It is more academically inclined as the students from Haledon and Prospect Park for the most part are more quasi-urban insofar as they don't want to be in school, they don't hope to proceed to college, and a better life. (I know because I've taught in both districts.)

And the court wouldn't allow North Haledon to break away and go to another district to educate its children. Mostly because Haledon and Prospect Park could not afford to finance its high school without North Haledon and its removal would result in de facto segregation.

This was more than 20 years ago. Here's the court's decision.
https://www.law.com/njlawjournal/almID/900005413163/

My point is that you could try to combine towns and services, but it doesn't always work to the efficiency in some situations of individual entities.