Gasoline and medicine should be the most scarce of resources, right? In the show, they make a big deal over how they're running out of bullets, but half of each episode is gunfire. Bullets don't go bad, but medicine and gasoline does. I mean medicine has expiration dates, and If i leave gas in my lawnmower in the fall, it won't start next spring. Are these plot holes, or has Eugene figured out how to refine gasoline?