More is possible than you might think
The basic idea of wifi targeting is serving ads on phones, where the location is determined by nearest wifi point. This is indeed possible. There is more, however. It’s technically possible to upload/insert IP addresses of - let’s say – branches of a certain brand/retailer. Then, when a consumer – physically visiting one of these branches – access the internet using free wifi, we can serve ads. Furthermore retargeting activities, based on these impressions, are possible.