So before the Infected attack your Compound, You get to choose to wait or to Bring it on... "Hey Walkers, Can you wait for a little? Gonna Equip my Survivors some Good Weapons to kill you off, then I gotta Speed up the Return of my Leader, Oh and I also have to take a Piss"
In an Apocalypse, Fuel is the Godly element that Fixes everything. It can Heal survivor Wounds, Grow Buildings, Pour it on a Pile of Junk and VOILA, It magically Disappears! You can even Upgrade ANYTHING with it! Anything is Possible with Fuel.