"... and paint QR codes on the ground at those spots ..."
This is what "Oh By Codes"[1] are for.
Instead of trying to paint a QR code, which is difficult, you can just chalk a 6 character code.
Further, you can create them on the fly without using a special tool - just a textarea on a simple webpage.
You can encode up to 4096 characters or a single URL redirect.
[1] https://0x.co
But people's phones will scan a QR code from the camera: they're much more likely to do that then type in a URL while walking.
That's certainly true - hence the extremely (almost minimally) short '0x.co' URL.
It's certainly not for every use-case ...
So 0x.co is tinyurl for strings?
Oh By is an “everything shortener”.
Well, it's a lookup table, limited to 6^N, where N is the number of legal characters (printable ASCII?).
They should make a tiny encoded image to save too. Typing something isn't as fast as point and shoot.
You can't scan them like a QR-code, which is kind of the point?