Players like being rewarded for play, so you should probably hand out rewards. This won’t be true for every game. Very small or simple worlds might not need reward qualities, and some styles of world might not suit. But for most games, you want to give out rewards.
Sometimes, these will be progress type things. You can get a Token of Appreciation for some actions, and you need to spend 10 of them to advance a major story. For this sort of thing, you need to plan out how much each quality is worth, and whether they can be exchanged for each other.
Another sort of reward is more like a souvenir or trophy – a mark that the character has done something in particular, like Hero of Broad Street or Silver-Tongued Devil. These are great. Players like them and they’re easy to do. But don’t go overboard – they become less valuable if you shower a character with them.