Sorry for not explaining it better haha.

Basically the way it works is, since so many people have the highest score, it picks them in a random order from the database every time. So every time the high score table refreshes itself (since it stays cached for a bit after each time) it'll change the order. Every night, that 10k goes to whoever is lucky enough to be in the top 10 at that time, so it's kind of a lucky draw.

One of the perks to having a complete collection :) Hope this clears it up a bit!