I used to live with someone who was obsessed with our milk supply - I would get calls all the time "have we got milk?"... "can you get some milk?"
I used to be so frustrated by this prioritising of milk - I mean there's more to life than milk isn't there....?!
I used to think "oh just buy some anyway!" - if it turns out we already have some, never mind, we will just have more! We can make a rice pudding or something if we end up with too much to use before it goes stale.
If it turns out we don't have any milk, never mind we can pop out again and get some or just manage without for a day.
Maybe I'm less affected than most because I don't have milk on cereal, but even so..