Food moths
Food moths - my personal summer enemies.
After bad experience with food moths, I watch out like a shooting dog when I see only one.
Now my advice:
Also in purchased goods, especially cereal items such as cereal, oatmeal, semolina, u. a. even in nuts, eggs of these beasts are already stored. For this reason, I put the boxed goods from the shopping bag once in the fridge, sometimes even in the frozen chest to destroy the eggs by cold. Since then, I rarely have trouble.
So I suspect that we not only get the food moths "delivered" from the outside through the window, but bring them straight from the shops for free.