When you open a fresh jar of peanut butter do you only work through one side until it is completely empty then start on the other side?
Or when you get those shallow tubs of hummus does it have to make it back home undisturbed? Then one of the baggers at the grocery store shoves it sideways into the bag completely ruining the symmetry.
My wife pours the milk into an empty bowl then brings the cereal box to her seat and pours it in one spoonful at a time. She insists this makes sense to do, and it's the only way she'll eat cereal.