If I was going to assume this was an intentional effect, my first thought would be that it is meant to do something to the limited volume of air passing through the region, or to people as they pass through that region.
Random hypothesis: it's a huge ionized-air antimicrobial filter running the circumference of a corridor that runs under the area, such that you instantly get "sanitized" as you pass through that corridor before entering e.g. a clean-room hardware assembly area.
I like the idea of a sterilizing force-field. (Not like, sterilizing, but... sterilizing...)
I enjoy speculation like that, but I am comfortable making the following generalization:
Corporations worth billions do not run physics experiments in densely populated areas, targeted at public land meant for public use.
Disregarding that common sense, some other wild assumptions:
Use static electricity as a subconscious cue to pay attention to a billboard nearby. Pavlovian training, too--associate your brand with a tingly feeling?
Super-high-power RFID/NFC reading!
Make a positioning system with increased accuracy using strong magnetic fields
Gauge perceptive abilities by demographic groups, and willingness to experiment with curious physical sensations.
Random hypothesis: it's a huge ionized-air antimicrobial filter running the circumference of a corridor that runs under the area, such that you instantly get "sanitized" as you pass through that corridor before entering e.g. a clean-room hardware assembly area.