and re: sybil resistance, if dynamic url QRs are deliberately apart at a distance as stickers, then maybe a nonsybil will go to the trouble of walking from kiosk to kiosk in a reasonable window to mint, otherwise index++ for tardiness. again, just riffing.
re stuff like this i just still go back to the question of when there would not be a top-down organizer—how common is that really? also, maybe i’m just biased with @event, given that we never really deal with this