I think the intention is to deliniate between 'western' and 'eastern' standards of living - in that context, Japan, South Korea and to an extent China are quite 'western'. This is as opposed to the Nepalese, who as the article says live on an annual income of ~USD$600.

This opens up another can of worms in implying that 'eastern' civilisations are poorer than western ones. I agree it is not a good use of the term but it's arguably better than 'first world' and 'third world' and I cannot think of a better equivalent.