It's no surprise that food companies employ scientists to create recipes that make their products addictive in order to increase sales.
This is a very deliberate tactic of the food industry, and something that goes highly unnoticed or ignored by people when discussing the obesity epidemic.
This is why I argue that yes, personal responsibility is a big part of being healthy, but there are other factors at play and they shouldn't be glossed over.
Dr. David Kessler does a great job of explaining this in "The End of Overeating", as does Michael Pollan in "The Omnivore's Dilemma"
Unfortunately, people counter these detailed arguments with anecdotal bullshyt like "well my cousin is fat and it's his own fault because blah blah blah..."