I seem to do this often, and I get really annoyed as I shop online and pick it up each week.
For some reason I always seem to run out of important things like milk and have to go again to the shops.
When I actually go into a supermarket I buy all sorts of things that I did not go in for, and hence I am better off shopping online -I should not really run out as I do the order as soon as I need something, but I do run out or need something for a recipe.
Finy, I like the photo you used for this question.! I buy the 1 litre 'long life' milks, & keeps 3 or 4 of them in the pantry for an emergency.. Very handy. They last for ages.