Don't know about the methodology, but this interestingly contradicts what "health food" culture would have you believe, esp. USA vs. Western Europe, and the relative place of countries like France.

In general, poorer and less connected to global economy means more vegetables? More affluent people people can't help the convenience of other foods? The other variable would be agriculture, and depth of living in capitalist economy including the older generations (which excludes Eastern Europe). I suspect in some places relatively "silent" and unpublicized demographics, like older people in the east, can skew the stats. I wonder who eats vegetables in the US (disclaimer, never been there) and what comes to mind is poor people outside metropolitan areas.