rice is an adjunct used quite often because it is much cheaper than malted barley.
Most asian beers I have tasted I would characterize as Light bodied highly carbonated with little or no Malt or hop flavor. It would not surprise me if a good majority of the grain bill was indeed rice or rice sugars.
I spent a year in Korea and I am basing my opinion on the two brands they had to offer Hite and OB.