Additionally, in the aggregate, it's simply not cost efficient to have multiple schools in one area, when one can service all the kids in a particular area. You now have two or more schools with football fields, gymnasiums, gym teachers and sports coaches, buildings, utility costs, parking lots, need two separate bus services for the schools.
If you are fiscal conservative, you don't support such things, unless it gives better results overall. It doesn't even with the current system like this. In the aggregate, if anything, we'd get better results if we didn't do this. Money would go further.