There are many ways to deal with this. There are libraries to share knowledge without violating copyright law. Schools reuse materials in order to reduce costs without violating copyright law. Many people will happily publish materials without directly charging for it or even receiving any compensation for it (e.g. advertising supported, creative commons licensed, etc.). Even though it isn't popular in many nations, many governments and humanitarian organizations will sponsor the development of books for education.

There is very little preventing you from accessing knowledge. True, you are prevented from accessing knowledge in a certain form (e.g. a particular book) -- but that is an entirely different issue.