An interesting question. It could be be that. Could also just be an example of what could happen in a country with a highly educated populace and highly-available broadband internet. If you have a choice of not just a few, but all teachers, why not pick "the best?" Certainly the best will be different for different people, but you can see how a few teachers could easily rise to the top. Night school might only be significant in that where to attend is completely up to the individual.