Consider how the crunch sound gets studied in food labs. They DO test it to make the eating experience better. But calling it "designed to make you want more" makes it sound EVIL. It's really just about sensory appeal, not addiction. Marketing uses all kinds of tricks, and sound is one of them. So while the crunch is on purpose, it's not a dark plot, just smart business.
What specific mechanical tests do they run on the crunch itself... like do they have machines that measure the perfect breaking point or sound frequency they're aiming for?