A "doomsday prepper" whom failed to stock up on booze?!!!!!
Remember how Howard only has "moonshined" vodka to offer as alcoholic beverage?
I mean, how could he possibly have NOT loaded up on beer, spirits and yes, even drugs (pot, heroin, anything you can snort/shoot/smoke/etc)?
It's the easiest to preserve (booze won't go to waste anytime soon if original container remains closed), and clearly one of the very first things you'll need to endure a prolonged stay underground, riding out whatever happened above ground (if a nuclear war broke out or an alien invasion too place, cirrhosis and addiction will be the LEAST of your problems).
So how could he have NOT done that?
That to me was the clearest sign that he was completely insane (I was almost waiting for him to say next "Oh, we're also out of toilet paper, so start getting used to eating with one hand..."