Because if you can't read, you will only know what your government wants you to. That's why Pol Pot killed all the teachers. These kids in the Madras schools are not reading the Koran. They are reciting what they have been told it says. Remember the videos of the kids in the Taliban schools? The Korans are in Arabic. They speak Pashtu in Afghanistan and they probably can't read that language either.
madrassahs not Madras ;-)