This is the worst kind of advertisement. Other ads just take up screen space and bandwidth: they displace more useful uses of these scarce resources, but they

This is the worst kind of advertisement. Other ads just take up screen space and bandwidth: they displace more useful uses of these scarce resources, but they don't cause any direct harm. By contrast, ads targeting people in the market for a good or service actively displace quality signals. In doing so they make quality uneconomical and thus destroy it. They make the world a worse place.