One area where this already exists is private schooling. In practice it leads to underfunding of public schools because the people with money are the people with political power. If their kids went to purely taxpayer-funded schools they would be higher quality and everyone would be getting a better education. (I know in the US things are a bit different, and there are are high quality public schools). The argument th…
I guess you are trying to sell the benefit of a highly-educated country to those who choose private schooling, and getting them to pay for this.
It boils down to how much are you willing to pay for another child's education and what is the acceptable standard of that education.
But if we think about the supply of education, a lot of it is about good teachers, and ultimately someone has to be stuck with the worst teacher in the country. And also class sizes.