Like e.g., L1; Kill 75 Owekos. So target is reached, report back to IFN rep, get a pat on the head & choose to take on the next level. Well there is the fun of doing it, but is that the only benefit? On Calypso you carry out the Daily Hunt, you get a token. What do you get on Arkadia, warm feeling for a job well done?
The more you kill, the better the rewards. You are also getting skill points while doing them and the chance to loot something nice. If you looted an Oweko Brain for example, that's a few thousand PED just there.
there is a list of rewards http://arkadiaforum.com/threads/mission-rewards-comparison.5205/ in this thread