You don't have to provide breakfast if you don't want to.
Your complaint was that no-one ate it or asked for things you don't provide. Milk can easily be decanted into a glass bottle with a lid. You can easily leave a half loaf instead of a full loaf.
Or you can provide nothing. I'm not sure it matters as all the Airbnb's I've stayed in (and now I'm into the 20s with different listings ) only 2 or 3 offering breakfast and it didn't guarantee them s five star whereas others without breakfast still got five stars.
I provide breakfast because I like to, it makes me feel good feeding people