There are already countries where international traffic costs more than domestic traffic. Ever rent a server in South Korea? International traffic is often limited to 1-3% of your monthly quota, depending on who your backbone provider is. Overage fees on international traffic usually run an order of magnitude higher than usual.
A policy like that has more than merely economic impact. It discourages people from interacting freely with foreign web services, contributing to a relatively isolated online culture. Korea might be doing this for economic and technical reasons only, but you can be sure that China has cultural and political agendas.
Bringing the same policy to consumers, on the other hand, would be insane. Even in Korea, consumers only pay a flat rate and the ISP absorbs any cost difference.
A policy like that has more than merely economic impact. It discourages people from interacting freely with foreign web services, contributing to a relatively isolated online culture. Korea might be doing this for economic and technical reasons only, but you can be sure that China has cultural and political agendas.
Bringing the same policy to consumers, on the other hand, would be insane. Even in Korea, consumers only pay a flat rate and the ISP absorbs any cost difference.