Wansink's book on Mindless Eating pretty much changed the way I view food: study after study after study show that we stop eating NOT when we know we're full, but based on a score of other cues. For instance, if we have a big pile of bones from chicken wings in front of us that is not cleared away, we will eat fewer. If we get a new glass every time we have another glass of wine, we will drink less. If snacks are served in one big bowl as opposed to many small bowls, we will take less food. And in a study with grad student volunteers at a test-restaurant, where a pump hidden beneath the table was hooked up to bowls of tomato soup and kept soup levels at a constant, people ate twice as much but felt like they ate less.

There are easy ways you can control overeating in your own home setting, but in restaurants, it becomes more complicated. They use giant plates to make it seem like you are eating less, they clear all plates and cups away, etc. Because in the end, food companies WANT you to eat more.

You can create your own visual stop signs at home (for instance, by putting chips into their own individual baggies rather than eating from the original bag) but getting companies to comply with a policy that would hack at their bottom line would be... difficult.