[makecheck]

It also happens in reverse: you tend to fill the size of plate you have, the size of glass, etc.

At buffets I either pick small plates or intentionally pick a small number of items regardless of how much of the plate is used.

With soda for instance I eventually realized that the main reason I was drinking a certain amount was a combination of the cup size and the straw. I switched to tiny cups that I drank from directly and found I could easily make that last a meal and have some left. Now I barely drink soda.