By 'split the prizes', Tigersclaw means that your entry fee is used to purchase prize boosters. These are all opened and the minis, loot cards, etc... are put in a pool with some other prizes the store provides, like promos or vinyl maps. We then draft from that pool in order of finish.
So first place takes whatever he or she wants from the pool first, and so on, then we loop back from last place up to first (so last place gets two picks, but usually by then it's all commons, loot and UDE point cards, green bases and die, these sort of things).
"The beatings will continue until morale has improved."
- Standard corporate management technique