[justboxing]

Since this seems to be the most accepted answer, I did some search on IP address re-targeting, and came across this, which is kind of creepy and annoying.

> Cookie-based retargeting uses online data while IP Targeting uses offline data, which is verified and drastically reduces the potential of non-human bot traffic. IP Targeting essentially takes the traditional direct mail approach and matches home and business postal addresses to computer/device IP addresses.

Source: http://www.accudata.com/why-ip-targeting-takes-the-cake/