Actually, I'm a Vegemite fan myself so not at all bothered by the shortage. Both Marmite and Vegemite are acquired tastes and something you either love or hate. I did get to thinking, though, what would I do if warned of an impending shortage of say coffee? Or chocolate? Would I rush out and stock up? I'd certainly buy some coffee to keep me going, but not too much as it's only good when fresh. Chocolate lasts a bit longer and it would be a good excuse to fill the pantry. And then there's cheese. I'd buy one or two soft cheeses and keep some hard cheeses in the fridge for a rainy day but eventually it would go off.
What food shortage would see you rushing to stock your shelves?