Why do you think random would be better? By doing it like this the best methods should be the winners, so everybody is more interested in writing something good. If it were random anyone wound enter with just a couple of sentences that wouldn't help much or anyone.
Also, the amount of time it takes t write a good topic, even if it's random or not, so there's not more work invoved into it.
If you have the time I'd advise you to enter and try, there haven't been that many submit so the chances of almost everyone winning something are quite high
:)) i bet