There's really only about three or four side quests that have actually done much for me so far: 1. Collecting the bones and then letting F.K.'s dog take them 2. Buying the map at the Milk Barn 3. Visiting The General at the Junkyard All give weapon and speed bonuses, the rest (so far) seem menial and borderline worthless. I could give a wet fart about collecting all the cards.