"From just those sources, PSY and his camp will rake in at least $8.1 million this year, according to an analysis by The Associated Press of publicly available information and industry estimates. But for online music sales in South Korea, he'll earn less than $60,000."

This is the important part of the article. He earns around US$0.00015 per song sold in his own country via online sales. He earns a hell of a lot more via Youtube and iTunes. What gets him up to 8M is other advertizing deals.