> Isn't is illegal, or impossible to order online, if you dont run windows in South Korea also?

So far, yes.

Things are beginning to change because Chinese consumers are crowding into Korean stores, both online and offline. Even the President is concerned that the old system hurts the economy by turning away potential buyers. Guess what, one of the perks of being a semi-authoritarian culture is that if the President complains about something, everyone rushes to find an alternative ;)

In any case, I wish there were more competition in the payment processing scene of my country as well. Most people haven't even heard of PayPal here, let alone newer and better alternatives. Perhaps once we get rid of the ActiveX dependence, more startups will be able to enter the market.