The advantage is social, stating "I've supported this art, this stick generates the QR code that proves that"
I still don't understand in how your device is supposed to state that.
All you have in your device is a bit-stream which the end-user can't trust, so in order to validate any kind of cryptographic data, you'd need some external "trusted" reference (PGP public keys, TLA certs, ...). At that point, the external verifier could just as well read the whole bitstream on its own (i.e. use a standard USB flash stick where you store the data and a signature alongside), couldn't it?
As for "displays it as a QR code", if it's displayed on the screen where the video is being played, then it's trivial to fake by putting the QR image in the video itself.
This solves the problem that many aren't reminded of the importance of supporting artists that create the art that they use.
You don't seem to live in the same world as mine: in my world, the MPAA and other control-obsessed profiteers spend millions of dollars reminding people of that as an excuse for their DRM abuses.
Stefan