Some businesses put them on their roofs.... so that ...astronauts can scan them?
Here's the Facebook HQ QR code:
Here's the roof of Phillips & Company... I have no idea what they do, but one could scan the QR code and find out!
However I have to agree with Dave Kellet's Arthur-the-duck in Sheldon about how QR codes seem like a transition technology.... kinda nifty, but in the end off-putting and/or clunky.
And as a bonus, here's a not-map-related-but-still-fun video about how a South Korean company boosted sales with an innovative sundial QR Code: