'For instance, if many people are eyeing a not-so-healthy dessert but not buying it, a store could place it at the checkout line so you see it again and "maybe your willpower breaks down," said Ryan Calo, a professor at the University of Washington School of Law and co-director of its Tech Policy Lab.
"Just because a company doesn't know exactly who you are doesn't mean they can't do things that will harm you," Calo said."