Haa~! Talking about learning something new everyday... thanks man!
Most price-winning pictures won't conform to the theme outright, just like some of the best essay are usually those that give a twist to the title. For example, if two student of equivalent literal competency were to write an essay titled "The Gift", and one wrote about a material gift from someone to celebrate a certain occasion, while another wrote about the birth of his/her cousin (the gift of life), which one do you think would be more impressive?
Photographs ain't just images of documentation. IMO, photographs themselves don't even have inherent value. Photographs are probably more like money, i.e. they only posess instrumental value, a mean to fulfill the ends. Most people want to be rich not so that they can swim in the cash. They wanna be rich, so that they could fulfill their other dreams, be it to drive a new car, to enjoy with a family, to go on a holiday or whatnot. Similarly, photographers don't wanna take pictures, so that they could swim around all the albums that they have taken.
Hence, while most of the thematic entries in competitions are usually the documentation ones (those that directly adhere to what the theme "ought to be"), what stands out usually are either those that are different, or those that manage to reveal the theme subtly and indirectly. And unless the documentation shots are truly impressive, I will actually question the credibility of the judge if they were to choose a documentation shot as a winner.
Here's another question though... are winners of competition necessary be a universally recognised "good" photograph?