Could actually be used for the opposite
With proper image-recognition software, it might actually be possible to do the opposite: remove ads from the real-world. The headset could be set up to do basic image recognition to compare what you are seeing to a database of advertisements (linked to your current location and the direction you are looking to reduce computational requirements) and replace it with a blank rectangle or maybe nice photos of cats or something. Maybe when you're traveling to a location, replace the image on the billboard with a maps and directions to the next way-point..
The advertising industry would hate it but Microsoft wouldn't care, the lion's share of their income is off of software sales, not ad sales like their competitors.