Maybe I'm going cross eyed from a long day, but looking at that result... how can Quaker oatmeal have 2g of protein and be 5% USRDA, while quinoa has 4g of protein yet 7% USRDA? Shouldn't that be 10% USRDA for quinoa?
Rounding. The RDA is 50 grams. So oatmeal's 2g is closer to 2.5g and quinoa's 4g is closer to 3.5g. At least that'd be my guess.
Probably rounding issues, maybe intentional. Food vendors are known to fudge numbers in the low digits, legally, which result in problems like this when you extrapolate.