You just explained that your behavior itself was odd (you are sick.) Have you considered that you've not normally done this and so you've never noticed that this is always what happens? My local grocery store has premade foods, like soups, and they get made in bursts and slowly run out over several days. So what you observed could be the norm.

I'm talking about the aisle, like the shelves being empty, not the premade section. But your point totally stands!