There's a good example. Some greedy gas stations blast ads while you're pumping gas: your money for gas isn't enough, they want to steal your attention as well. But a customer may wear in-ear headphones that normally play music, but can also play nothing, let the outer sounds in, except for the speech frequencies silenced by the active noise suppression. It so happens that ads rely on speech frequencies to steal attention. Problems begin when the ads platform that gas stations use and the manufacturer of those smart headphones is the same company.